fix(webapp): upgrade posthog-node to v5, drop axios + stale override #6778

Job	Run time
Detect changes	3s
sdk-compat / Deno Runtime	2m 37s
sdk-compat / Cloudflare Workers	2m 37s
typecheck / typecheck	7m 14s
sdk-compat / Node.js 20.20 (ubuntu-latest)	2m 31s
e2e-webapp / 🧪 E2E Tests: Webapp	3m 56s
sdk-compat / Bun Runtime	2m 30s
packages / 🧪 Unit Tests: Packages (1, 1)	12m 13s
e2e / 🧪 CLI v3 tests (windows-latest - npm)	3m 55s
e2e / 🧪 CLI v3 tests (ubuntu-latest - pnpm)	2m 5s
webapp / 🧪 Unit Tests: Webapp (2, 8)	5m 8s
webapp / 🧪 Unit Tests: Webapp (1, 8)	6m 27s
webapp / 🧪 Unit Tests: Webapp (8, 8)	7m 19s
webapp / 🧪 Unit Tests: Webapp (5, 8)	6m 19s
webapp / 🧪 Unit Tests: Webapp (6, 8)	4m 22s
internal / 🧪 Unit Tests: Internal (1, 8)	7m 37s
internal / 🧪 Unit Tests: Internal (4, 8)	6m 18s
internal / 🧪 Unit Tests: Internal (6, 8)	5m 50s
internal / 🧪 Unit Tests: Internal (5, 8)	7m 18s
internal / 🧪 Unit Tests: Internal (2, 8)	13m 26s
internal / 🧪 Unit Tests: Internal (7, 8)	6m 10s
webapp / 🧪 Unit Tests: Webapp (7, 8)	9m 35s
webapp / 🧪 Unit Tests: Webapp (4, 8)	9m 6s
webapp / 🧪 Unit Tests: Webapp (3, 8)	4m 15s
e2e / 🧪 CLI v3 tests (ubuntu-latest - npm)	1m 54s
internal / 🧪 Unit Tests: Internal (8, 8)	5m 31s
sdk-compat / Node.js 22.12 (ubuntu-latest)	2m 29s
internal / 🧪 Unit Tests: Internal (3, 8)	9m 21s
e2e / 🧪 CLI v3 tests (windows-latest - pnpm)	4m 57s
webapp / 📊 Merge Reports	53s
packages / 📊 Merge Reports	25s
internal / 📊 Merge Reports	29s
All PR Checks	3s
	2h 44m 53s

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