coordinator: make gitignore/PLAN.md setup idempotent, run every phase

Old i===0 && !resuming gate meant this only ran on a fresh start -- every
run this session was a resume, so poiman's branch never got the harness
gitignore rules, and portfolio's PLAN.md stayed tracked from before the
rule existed (gitignore doesn't affect already-tracked files). Now checks
and fixes both on every phase instead of once at genesis.

k8s/apps/agent-pod/coordinator-configmap.yaml

@@ -752,31 +752,47 @@ data:
           return finish("branch-crashed");
         }
     
-        if (i === 0 && !resuming) {
-          const gitignoreAdditions = [
-            "",
-            "# agent-harness: build artifacts and vendored archives never belong in source control",
-            "*.tar.gz",
-            "*.tgz",
-            "*.crate",
-            "*.zip",
-            "*.bin",
-            "*.whl",
-            "vendor/",
-            "node_modules/",
-            "",
-            "# agent-harness: task/phase completion sentinel files, harness bookkeeping only",
-            ".task-result-*",
-            ".phase-result-*",
-            ".stage-done-*",
-            "",
-            "# agent-harness: PLAN.md is per-task planner scratch state, never a deliverable",
-            "PLAN.md",
-          ].join("\n");
-          fs.appendFileSync(path.join(cwd, ".gitignore"), gitignoreAdditions + "\n");
+        // Idempotent and run every phase, NOT gated on a fresh (non-resumed)
+        // start -- every run this session was a resume, so the old i===0 &&
+        // !resuming gate meant this setup permanently never ran on poiman's
+        // branch, and portfolio's PLAN.md stayed tracked from before this rule
+        // ever existed (gitignore has no effect on an already-tracked file --
+        // observed live: it kept getting swept back in by every `git add -A`
+        // regardless of the ignore rule). Check-and-fix on every phase instead
+        // of once-at-genesis so a repo that's missing either self-heals on its
+        // very next run rather than carrying the gap forever.
+        const gitignorePath = path.join(cwd, ".gitignore");
+        const currentGitignore = fs.existsSync(gitignorePath) ? fs.readFileSync(gitignorePath, "utf8").split("\n") : [];
+        const requiredGitignoreLines = [
+          "*.tar.gz",
+          "*.tgz",
+          "*.crate",
+          "*.zip",
+          "*.bin",
+          "*.whl",
+          "vendor/",
+          "node_modules/",
+          ".task-result-*",
+          ".phase-result-*",
+          ".stage-done-*",
+          "PLAN.md",
+        ];
+        const missingGitignoreLines = requiredGitignoreLines.filter((line) => !currentGitignore.includes(line));
+        if (missingGitignoreLines.length > 0) {
+          fs.appendFileSync(
+            gitignorePath,
+            "\n# agent-harness: build artifacts, vendored archives, and harness bookkeeping never belong in source control\n" +
+              missingGitignoreLines.join("\n") +
+              "\n"
+          );
           await runGit(cwd, ["add", ".gitignore"]);
           await runGit(cwd, ["commit", "-m", "chore: broaden .gitignore for agent-run artifacts"]);
         }
+        const trackedFiles = await runGit(cwd, ["ls-tree", "-r", "HEAD", "--name-only"]);
+        if (trackedFiles.out.split("\n").includes("PLAN.md")) {
+          await runGit(cwd, ["rm", "--cached", "PLAN.md"]);
+          await runGit(cwd, ["commit", "-m", "chore: untrack PLAN.md (already gitignored, was committed pre-rule)"]);
+        }
     
         await runPhase(cwd, baseBranch, phaseBranch, phaseTasks, pool, repoId, pipelineSession);