feat(adf): add source LOC budget enforcement to catch godobject drift

[stackbilt-admin]

Summary

Charter ADF checks can pass while very large source files continue growing, unless teams explicitly configure additional LOC sync entries.

In practice this let src/index.ts in opsbrain reach 1600+ LOC without the Charter gate failing, despite repo governance intent to avoid godobjects.

Why this matters

Teams can believe they are fully covered by Charter's default pre-commit gate, but still miss high-risk architecture drift (godobject growth) because only entry_loc is enforced by default.

Repro (from real repo usage)

1. Repo has Charter wiring + pre-commit hook enabled.
2. Add many routes to one entry file (src/index.ts) until it exceeds intended team threshold.
3. Run:
   • npx charter doctor --adf-only --ci --format text
   • npx charter adf evidence --auto-measure --ci
4. Output still reports PASS with entry_loc only, unless custom sync constraints were manually configured.

Observed output shape

• Constraints: [ok] entry_loc: 0 / 500 [lines] -- PASS
• No default warning/failure about oversized runtime source files.

Expected

At minimum, one of:

• A built-in optional policy profile for source LOC ceilings (for common patterns like src/index.ts, route files, service classes), or
• A clear warning during doctor/evidence when only entry_loc is enforced and no runtime LOC ceilings exist, or
• A first-class Charter config block to define per-path LOC budgets with sane defaults + explicit fail/warn behavior.

Proposed acceptance criteria

• Add a documented + supported way to enforce source-file LOC budgets without custom scripts.
• charter doctor surfaces when LOC coverage is effectively absent for runtime source files.
• Teams can select warn vs fail policy per path pattern.

[stackbilt-admin]

Shipped in #194 (commit e1dcbd9). Quick usage + one scoping note so the rollout isn't surprising:

How to use — declare per-path budgets in .charter/config.json:

{
  "locBudgets": {
    "defaultWarn": 300,
    "defaultFail": 600,
    "paths": [
      { "pattern": "src/index.ts", "warn": 200, "fail": 500, "reason": "entry should stay thin" },
      { "pattern": "src/**", "warn": 300, "fail": 600 }
    ]
  }
}

charter doctor then measures matching files. Over the fail ceiling → WARN (fails CI under --ci); over warn only → advisory INFO (never fails CI). First matching pattern wins; per-rule ceilings fall back to the defaults.

Scoping note (important): enforcement lives in charter doctor — the pre-commit/CI gate that loads .charter/config.json. charter adf evidence --auto-measure is intentionally unchanged; it's manifest-driven (reads .ai, not .charter) and still reports only the metrics declared in manifest.adf. So re-running your original adf evidence repro will still show entry_loc only — that's expected; the god-object coverage is charter doctor --adf-only --ci.

Opt-in / non-breaking: with no locBudgets block, nothing is enforced — doctor just emits a soft INFO nudge that only entry_loc is covered.

Docs: docs/cli-reference.md → charter doctor → "Source LOC budgets". Closing as delivered; reopen if the doctor path doesn't cover your case.