feat: allocate emissions by repository share

[CaptainTimon]

Summary

Folded #1215 into one atomic PR, per maintainer feedback on the sliced PRs.

This converts repository allocation from an unbounded per-PR weight multiplier into bounded repo-level emission_share allocation:

• Rename live repo config from weight to emission_share, with [0, 1] per-repo validation and sum(emission_share) <= 1.0 validation.
• Add issue_discovery_share ([0, 1], default 0.5) and set entrius/oc-1 to 0.0 for issue discovery.
• Collapse top-level emissions to OSS_EMISSION_SHARE = 0.90 and ISSUES_TREASURY_EMISSION_SHARE = 0.10; remove fixed issue-discovery/recycle emission constants.
• Remove repository weighting from PR earned-score, open-PR collateral, mirror PR multiplier calculation, and issue-discovery earned-score calculation.
• Preserve old storage/adapter fields as neutral compatibility fields instead of doing schema churn in this PR.
• Add allocate_repo_scoring_pool: each repo receives at most emission_share * 90%; PR/issue sides split by issue_discovery_share, empty side spills only within the same repo, fully inactive repo slices and registry slack recycle to UID 0.
• Persist scored issue-discovery Issue objects on MinerEvaluation.discovered_issues so aggregation uses real per-repo issue-discovery evidence, not global normalized arrays.
• Wire validator forward pass and gitt miner score to allocate from raw per-repo score evidence.

Related Issues

Closes #1215.

Prior PR Analysis

Reviewed the existing single-PR attempts #1217, #1218, #1219, and #1223 plus the closed slice PRs #1220, #1222, #1224-#1232.

This PR keeps the integrated/atomic shape requested by the maintainer, but avoids two risks I saw in those attempts:

• It does not remove persistence columns or adapter fields in the same monetary-policy change; old repo_weight_multiplier fields stay neutral for compatibility.
• It explicitly stores issue-discovery scored issues on MinerEvaluation, so repo-level aggregation can see real issue-discovery scores from the active path instead of relying on a non-existent per-repo aggregate field or already-normalized arrays.

Type of Change

• Bug fix
• New feature
• Refactor
• Documentation
• Other (describe below)

Emission policy / reward allocation change.

Testing

• Tests added/updated
• Manually tested

Commands run:

uv run pytest tests/validator/test_load_weights.py tests/validator/test_emission_share_allocation.py tests/validator/oss_contributions/mirror/test_scored_pr.py tests/validator/oss_contributions/mirror/test_scoring.py tests/validator/issue_discovery/test_scan.py tests/cli/test_miner_score.py -q
uv run ruff check gittensor/constants.py gittensor/validator/utils/load_weights.py gittensor/validator/emission_allocation.py gittensor/validator/forward.py gittensor/classes.py gittensor/validator/oss_contributions/mirror/scored_pr.py gittensor/validator/oss_contributions/mirror/scoring.py gittensor/validator/issue_discovery/scan.py gittensor/validator/oss_contributions/scoring.py gittensor/cli/miner_commands/score.py tests/validator/test_load_weights.py tests/validator/test_emission_share_allocation.py tests/validator/oss_contributions/mirror/test_scoring.py tests/validator/oss_contributions/mirror/test_scored_pr.py
uv run ruff format --check gittensor/constants.py gittensor/validator/utils/load_weights.py gittensor/validator/emission_allocation.py gittensor/validator/forward.py gittensor/classes.py gittensor/validator/oss_contributions/mirror/scored_pr.py gittensor/validator/oss_contributions/mirror/scoring.py gittensor/validator/issue_discovery/scan.py gittensor/validator/oss_contributions/scoring.py gittensor/cli/miner_commands/score.py tests/validator/test_load_weights.py tests/validator/test_emission_share_allocation.py tests/validator/oss_contributions/mirror/test_scoring.py tests/validator/oss_contributions/mirror/test_scored_pr.py
uv run pytest -q

Results:

• Focused suite: 195 passed
• Full suite: 729 passed

Checklist

• Code follows project style guidelines
• Self-review completed
• Changes are documented (if applicable)

[anderdc]

Closing — contributor is not a registered subnet miner.