feat(kvb-check-gate): prove 90/5 by every make test* target on the exact head

The operator's rule (2026-11-03): nothing is declared 90/5 before every make test* target of the project ran green on the exact head. kvb-check-gate holds it as the single source and gate.py backs it: list parses the Makefile make would read and its includes statically (never running make, whose $(shell ...) would execute), status reports green, red or missing per target for HEAD and says gate: green only when all are green on a clean tracked tree, and run executes known targets one by one as make -C with output written straight to a log (no pipe hiding the exit code), marking a target red on a non-zero exit, a make: *** or make[N]: *** line, or a project --fail-regex such as infinito-nexus' FAILED TARGETS. Results live per sha in the git common dir under a lock, shared by linked worktrees; a new commit or a target that edits tracked files invalidates them.

kvb-check-confidence and kvb-git-pr-label point to gate.py status instead of restating the rule; the README places the skill. test_gate covers parsing with includes, green, red and fail-pattern runs, stale results after a commit, dirty trees, worktrees and usage errors.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

README.md

@@ -62,6 +62,7 @@ flowchart LR
   check --> check_principles[kvb-check-principles]
   check --> check_confidence[kvb-check-confidence]
   check --> check_break_risk[kvb-check-break-risk]
+  check --> check_gate[kvb-check-gate]
   org --> org_organize[kvb-org-organize]
   org --> org_split[kvb-org-split]
   org --> org_coordinate[kvb-org-coordinate]
@@ -155,6 +156,7 @@ flowchart LR
     sceptic[kvb-check-principles]
     confidence[kvb-check-confidence]
     break_risk[kvb-check-break-risk]
+    gate[kvb-check-gate]
   end
   subgraph cat_org [org]
     democracy[kvb-org-organize]
@@ -227,6 +229,9 @@ flowchart LR
   commit_no_verify --> advocate
   advocate --> dialectic
   confidence --> break_risk
+  confidence --> gate
+  pr_label --> gate
+  gate --> democracy
   confidence -. objective .-> autotune
 
   coordinate --> democracy