docs: add VERSIONING.md codifying SemVer + lockstep release strategy

[roman1887]

What & why

Codifies the versioning & release strategy resolved in #211 as the durable source of truth.

Decisions captured:

• Strict SemVer with Actyze-specific major/minor/patch definitions
• Lockstep — all 6 Actyze images share one version == chart appVersion, bumped together
• Baseline 0.1.0 (pre-1.0)
• Pin, never float — user-facing chart + compose pin to immutable version tags, pullPolicy: IfNotPresent; never latest/main-llm-flex
• Release process — Conventional Commits → release-drafter → publish tag → CI builds/pushes X.Y.Z images → bump appVersion + pin → chart release
• Two-chart sync rule — helm-charts/ (canonical, user-facing) and dashboard/.helm-charts/ (DO demo copy) kept in sync manually; update both in the same change set

Also documents a blocker: release-build.yml omits the 3 prediction workers and points at two non-existent Dockerfile paths (docker/Dockerfile.frontend, models/schema-service/Dockerfile) — must fix before cutting v0.1.0.

Refs #211

🤖 Generated with Claude Code

[github-actions]

Claude Code Review

PR Review: docs: add VERSIONING.md + observability instrumentation

Note: The PR title says "add VERSIONING.md" but the diff contains no VERSIONING.md. This is a substantial observability instrumentation PR bundled under a misleading title. The review covers what was actually changed.

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1. Security 🔴

SSRF / error message injection — nexus/main.py lines ~253–261 and ~295–303

The f-string error messages in both /readyz and /api/health/predictions interpolate str(e) directly into a raw JSON string returned to the client:

content=f'{{"status": "not_ready", "message": "{str(e)}"}}',

If the exception message contains a double-quote, this produces malformed JSON. More importantly, it leaks internal exception text (stack details, hostnames, connection strings) to any unauthenticated caller—these are public probes. Use a fixed message or json.dumps to serialize safely:

import json
content=json.dumps({"status": "not_ready", "message": "Service initialization failed"}),

Same pattern in /api/health/predictions. Strip str(e) from both responses.

/metrics endpoint is unauthenticated — nexus/main.py

GET /metrics now exposes Prometheus metrics without any auth check. Metrics can reveal internal topology, query patterns, user counts, and LLM model names. Either place it behind require_viewer or restrict it to an internal-only port/path at the network layer. At minimum, document the exposure.

/api/health/predictions is unauthenticated — nexus/main.py

This endpoint returns worker health status to anyone. It should be restricted, or at least confirm this is intentional. The old /health was similarly open, but this one exposes more service topology.

Credentials visible in health-check error logs — observability_init.py (all three workers)

In check_postgres(), a caught exception is logged with error=str(e). psycopg2 exceptions routinely embed the DSN (host, port, database, user) in the message. This will write connection-string fragments to structured logs. Sanitize before logging:

logger.warning("postgres_health_check_failed", error="Connection refused")  # not str(e)

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2. Correctness 🟡

observability_init.py — duplicate, conflicting sys.path manipulation

All three worker copies contain:

sys.path.insert(0, os.path.join(os.path.dirname(__file__), '../../shared'))
# ...imports happen here...
sys.path.insert(0, '/app/shared_obs')

The second sys.path.insert happens after the imports that depend on the first path. The /app/shared_obs path is a hardcoded container-internal path that silently does nothing in dev but shadows modules in production. This is fragile and the intent is unclear. Remove it or document it.

asyncio imported but never used — all three observability_init.py

import asyncio  # inside setup_health_endpoints

This import is dead code in every copy.

check_trino() in health checks uses synchronous trino.dbapi calls inside an async def

The cursor.execute("SELECT 1") call is blocking. On a slow or unreachable Trino this will block the event loop during a readiness probe, potentially cascading into timeouts. Wrap in asyncio.to_thread() or use a true async Trino client.

Same issue in check_postgres() — psycopg2.connect() is blocking

Same fix: wrap in asyncio.to_thread().

schema-service/schema_service.py — old /health endpoint removed, but its data is gone

The original /health returned operationally useful data:

{"last_updated": "...", "total_schemas": 42, "index_size": 1500}

The replacement from setup_health_endpoints() returns only {"status": "healthy"}. This is a regression for operators monitoring schema-service state. The rich data should be preserved in /health or /ready.

nexus/main.py — generate_latest() called without registry argument

return Response(content=generate_latest(), ...)

Without a registry argument this uses the default Prometheus registry, not metrics_registry imported from app.metrics. Inconsistent with how the worker observability_init.py files call generate_latest(metrics_registry). Pass the registry explicitly.

useFirstContentfulPaint hook measures wall time, not FCP

trackPerformance(`fcp_${featureName}`, performance.now(), 'ms', ...)

performance.now() here is milliseconds since navigation start, not duration since the element appeared. The metric name says FCP but the value is an absolute timestamp. Use performance.now() - startTimeRef.current or the PerformanceObserver API for real FCP.

MetricsContext used in async endpoints but appears to be a context manager wrapping synchronous handler.train() calls

If MetricsContext.__exit__ swallows exceptions before the except ValueError clause runs, error-path metrics will never be recorded. The pattern records metrics inside the with block on success, then records them again in the except blocks—this is a double-record on error if the context manager doesn't re-raise immediately. Verify MetricsContext re-raises all exceptions.

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3. Code Quality 🟡

Tripled observability_init.py — identical files in three worker directories

All three copies are byte-for-byte identical (index 0000000..3315c55 on all three). This is the anti-pattern the shared observability/ library was created to avoid. Extract to shared/observability/python/worker_init.py (it already imports from there) and import it from one place. The current approach guarantees drift.

nexus/app/audit_logger.py — unused imports

import json

json is imported but never used. Remove it.

nexus/app/api.py — imports inside function bodies

async def generate_sql(...):
    import time
    from app.metrics import record_nl_query
    from app.audit_logger import audit_logger
    from app.logging import get_request_id

These are module-level dependencies; import them at the top of the file. Deferred imports inside hot-path request handlers add overhead and obscure dependencies.

nexus/main.py — global mutable state for readiness

app_started = False

A bare module-level boolean is not thread-safe and will not survive a reload or multi-worker deployment. Use an asyncio.Event or the existing orchestration_service health check as the authoritative source of readiness.

frontend/src/utils/observability-init.ts — navigator.platform is deprecated

navigator.platform has been deprecated in all major browsers. Remove it from the startup debug log.

useQueryObservability.ts — any cast for status code

const statusCode = (err as any)?.response?.status || 500;

This bypasses TypeScript's type system. Define a typed error interface or use a type guard.

frontend/src/components/ErrorBoundary.tsx — duplicate import

import { trackError } from '../utils/observability-init';
import { error as logError } from '../utils/observability-init';

Both imports are from the same module. Combine into one import statement.

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4. Testing 🟠

No tests are added for any of the new code:

• No pytest tests for audit_logger.py, metrics.py, or the new middleware in nexus/main.py
• No Jest tests for ErrorBoundary, useQueryObservability, or usePerformanceTracking
• The health endpoint changes (/healthz, /readyz, /health deprecation) have no test coverage

The project standards require tests for new features. The /readyz JSON-injection bug above would have been caught by a test.

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5. AGPL Compliance ✅ / 🟡

• New Python files (audit_logger.py, metrics.py, logging.py, workers' observability_init.py) are missing the # SPDX-License-Identifier: AGPL-3.0-only header required by project standards. The Python worker observability_init.py files have it; the nexus files do not.
• shared/observability/__init__.py has no license header.
• schema-service/app/observability_init.py has no license header.
• All new TypeScript/JS files correctly include the SPDX header. ✅
• No incompatible dependencies introduced. ✅

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Summary

Area	Status
Security	🔴 SSRF/injection in error responses, unauthenticated metrics, credential leak in health logs
Correctness	🟡 Blocking I/O in async probes, FCP metric is wrong, registry mismatch in /metrics
Code Quality	🟡 Tripled identical files, imports inside hot path, JSON import unused
Testing	🟠 No tests added for any new code
AGPL headers	🟡 Missing on several new Python files

Block on the SSRF/JSON-injection in /readyz and /api/health/predictions before merge. The blocking I/O in health probes and the tripled observability_init.py should be addressed in this PR rather than deferred.

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Automated review by Claude Sonnet 4.6 | Context: CLAUDE.md + README.md