fix: Stop milestone completion git archaeology

src/resources/extensions/sf/prompts/complete-milestone.md

@@ -18,7 +18,7 @@ Then:
 1. Use the **Milestone Summary** output template from the inlined context above
 2. Inspect the inlined or linked **MILESTONE VALIDATION** verdict. If the verdict is not `pass` (including `needs-attention` or `needs-remediation`), record it as a **verification failure** and follow the failure path. Do NOT call `sf_complete_milestone` for a non-pass validation verdict.
 3. {{skillActivation}}
-4. **Verify code changes exist.** Run `git diff --stat HEAD $(git merge-base HEAD main) -- ':!.sf/'` (or the equivalent for the integration branch). If no non-`.sf/` files appear in the diff, the milestone produced only planning artifacts and no actual code. Record this as a **verification failure**.
+4. **Verify implementation evidence exists.** Use the inlined validation verdict and slice summaries as the primary proof that implementation happened. If a slice summary lists non-`.sf/` key files, accepted verification commands, or committed work, that satisfies code-change verification for already-integrated milestone work. Run only `git status --short` to check for unresolved local changes. Do **not** inspect git history, compute merge bases, or run branch-diff archaeology unless the validation verdict and slice summaries are missing or contradictory. If no slice summary or validation evidence names implementation files, record this as a **verification failure**.
 5. Verify each **success criterion** from the milestone definition in `{{roadmapPath}}`. For each criterion, confirm it was met with specific evidence from slice summaries, test results, or observable behavior. Record any criterion that was NOT met as a **verification failure**.
 6. Verify the milestone's **definition of done** — all slices are `[x]`, all slice summaries exist, and any cross-slice integration points work correctly. Record any unmet items as a **verification failure**.
 7. If the roadmap includes a **Horizontal Checklist**, verify each item was addressed during the milestone. Note unchecked items in the milestone summary.
@@ -50,7 +50,7 @@ If work falls into the second bucket, do not fail the milestone just because it
 **Success path** (all verifications passed — continue with steps 10–14):
 
 10. For each requirement whose status changed in step 9, call `sf_requirement_update` with the requirement ID and updated `status` and `validation` fields — the tool regenerates `.sf/REQUIREMENTS.md` automatically. Do this BEFORE completing the milestone so requirement updates are persisted.
-11. **Persist completion through `sf_complete_milestone`.** Call it with the parameters below. The tool updates the milestone status in the DB, renders `{{milestoneSummaryPath}}`, and validates all slices are complete before proceeding.
+11. **Persist completion through `sf_complete_milestone`.** Call it with the parameters below as soon as steps 2, 4, 5, 6, and 10 are satisfied. Do not keep reading historical commits or re-running broad test suites after the requirements are updated. The tool updates the milestone status in the DB, renders `{{milestoneSummaryPath}}`, and validates all slices are complete before proceeding.
 
    **Required parameters:**
    - `milestoneId` (string) — Milestone ID (e.g. M001)

src/resources/extensions/sf/session-forensics.ts

@@ -449,6 +449,13 @@ function formatRecoveryPrompt(
 		"4. Run the narrowest verification command that proves the resumed work.",
 		"5. Complete the unit, or explicitly report the blocker with the exact remaining file/command.",
 	);
+	if (unitType === "complete-milestone") {
+		sections.push(
+			"",
+			"### Complete-Milestone Recovery Rule",
+			"For milestone closeout, do not inspect git history or compute merge-base diffs on resume. Use the existing validation verdict, slice summaries, and already-run requirement updates. If validation passed and all slices are complete, call `sf_complete_milestone` with a concise summary instead of continuing branch archaeology.",
+		);
+	}
 
 	return sections.join("\n");
 }

src/resources/extensions/sf/tests/complete-milestone.test.ts

@@ -205,6 +205,30 @@ describe("complete-milestone", () => {
 		);
 	});
 
+	test("prompt avoids branch-diff archaeology for already-integrated milestone work", () => {
+		const prompt = loadPromptFromWorktree("complete-milestone", {
+			workingDirectory: "/tmp/test-project",
+			milestoneId: "M001",
+			milestoneTitle: "Integrated Work Test",
+			roadmapPath: ".sf/milestones/M001/M001-ROADMAP.md",
+			inlinedContext: "context",
+		});
+
+		assert.ok(
+			prompt.includes("Use the inlined validation verdict and slice summaries"),
+			"prompt should use inlined validation and slice summaries as implementation proof",
+		);
+		assert.ok(
+			/Do\s+\*\*not\*\*\s+inspect git history/.test(prompt) ||
+				prompt.includes("Do not inspect git history"),
+			"prompt should explicitly forbid git-history archaeology",
+		);
+		assert.ok(
+			!prompt.includes("git diff --stat HEAD $(git merge-base HEAD main)"),
+			"prompt must not use a merge-base diff that is empty on integration branch",
+		);
+	});
+
 	test("prompt treats non-pass validation verdict as a completion blocker", () => {
 		const prompt = loadPromptFromWorktree("complete-milestone", {
 			workingDirectory: "/tmp/test-project",