feat(dashboard): wire cred-proxy-block approval to real apply (PRD 0014)

Phase 3 of PRD 0014. dashboard.approve() now does the real
remediation for cred-proxy-block proposals:

- Calls apply_routes_change(slug, file_to_apply) which fetches the
  current routes.json from the running sidecar, validates the new
  JSON, docker cp's it in, and SIGHUPs the sidecar.
- Audit entry's diff is now the real before→after from the apply
  return — not the empty-string placeholder 0013 wrote.
- On apply failure (CredProxyApplyError): no response file, no
  audit entry. Proposal stays pending so the operator can fix the
  input and retry. The TUI's key handlers catch the exception and
  surface the message in the status line.
- pipelock-block + capability-block remain no-op approvals; their
  remediation lands in PRDs 0015 + 0016 and the audit diff stays
  empty until then.
- reject path unchanged: no apply, audit entry with empty diff.

Tests stub apply_routes_change at the dashboard module level so the
unit suite doesn't need a running sidecar; integration test in
Phase 5 covers the real docker exec/cp/SIGHUP plumbing.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

tests/unit/test_dashboard.py

@@ -1,8 +1,12 @@
-"""Unit: dashboard headless paths (PRD 0013 phase 4).
+"""Unit: dashboard headless paths (PRD 0013 phase 4, PRD 0014).
 
 The curses TUI itself isn't exercised here — these tests cover the
 discovery + approve/reject + audit-write paths that the TUI's key
 handlers call into.
+
+apply_routes_change is stubbed at the dashboard module level so the
+tests don't need a running cred-proxy sidecar; the real docker
+exec/cp/SIGHUP plumbing is covered by the integration test.
 """
 
 import os
@@ -12,6 +16,7 @@ from datetime import datetime, timezone
 from pathlib import Path
 
 from claude_bottle import supervise
+from claude_bottle.backend.docker.cred_proxy_apply import CredProxyApplyError
 from claude_bottle.cli import dashboard
 from claude_bottle.supervise import (
     Proposal,
@@ -110,8 +115,15 @@ class TestDiscoverPending(_FakeHomeMixin, unittest.TestCase):
 class TestApproveReject(_FakeHomeMixin, unittest.TestCase):
     def setUp(self):
         self._setup_fake_home()
+        self._original_apply = dashboard.apply_routes_change
+        # Default stub: succeed with deterministic before/after so the
+        # audit log shows a non-empty diff.
+        dashboard.apply_routes_change = lambda slug, content: (
+            '{"routes": []}\n', content,
+        )
 
     def tearDown(self):
+        dashboard.apply_routes_change = self._original_apply
         self._teardown_fake_home()
 
     def _enqueue(self, tool: str = TOOL_CRED_PROXY_BLOCK):
@@ -166,6 +178,96 @@ class TestApproveReject(_FakeHomeMixin, unittest.TestCase):
         self.assertEqual(0, len(read_audit_entries("cred-proxy", "dev")))
 
 
+class TestCredProxyApplyWiring(_FakeHomeMixin, unittest.TestCase):
+    """PRD 0014 Phase 3: approve() on a cred-proxy-block proposal
+    must call apply_routes_change with the right args and surface
+    its failures."""
+
+    def setUp(self):
+        self._setup_fake_home()
+        self._original_apply = dashboard.apply_routes_change
+
+    def tearDown(self):
+        dashboard.apply_routes_change = self._original_apply
+        self._teardown_fake_home()
+
+    def _enqueue_cred_proxy(self, proposed: str = '{"routes": []}\n'):
+        p = Proposal.new(
+            bottle_slug="dev", tool=TOOL_CRED_PROXY_BLOCK,
+            proposed_file=proposed,
+            justification="need a route",
+            current_file_hash=sha256_hex(proposed),
+            now=FIXED,
+        )
+        qdir = supervise.queue_dir_for_slug("dev")
+        qdir.mkdir(parents=True, exist_ok=True)
+        supervise.write_proposal(qdir, p)
+        return dashboard.QueuedProposal(proposal=p, queue_dir=qdir)
+
+    def test_cred_proxy_block_calls_apply_with_proposed_file(self):
+        calls = []
+        dashboard.apply_routes_change = lambda slug, content: (
+            calls.append((slug, content)) or ("before", content)
+        )
+        qp = self._enqueue_cred_proxy(proposed='{"routes": [{"path": "/new/"}]}\n')
+        dashboard.approve(qp)
+        self.assertEqual(1, len(calls))
+        slug, content = calls[0]
+        self.assertEqual("dev", slug)
+        self.assertEqual('{"routes": [{"path": "/new/"}]}\n', content)
+
+    def test_modify_passes_final_file_to_apply(self):
+        calls = []
+        dashboard.apply_routes_change = lambda slug, content: (
+            calls.append(content) or ("before", content)
+        )
+        qp = self._enqueue_cred_proxy()
+        dashboard.approve(qp, final_file='{"routes": [{"path": "/edited/"}]}\n', notes="tweaked")
+        self.assertEqual(['{"routes": [{"path": "/edited/"}]}\n'], calls)
+
+    def test_apply_failure_blocks_response_and_audit(self):
+        dashboard.apply_routes_change = lambda slug, content: (_ for _ in ()).throw(
+            CredProxyApplyError("docker exec failed")
+        )
+        qp = self._enqueue_cred_proxy()
+        with self.assertRaises(CredProxyApplyError):
+            dashboard.approve(qp)
+        # No response file (proposal stays pending).
+        self.assertEqual(
+            [qp.proposal.id],
+            [p.id for p in supervise.list_pending_proposals(qp.queue_dir)],
+        )
+        # No audit entry.
+        self.assertEqual([], read_audit_entries("cred-proxy", "dev"))
+
+    def test_real_diff_lands_in_audit(self):
+        dashboard.apply_routes_change = lambda slug, content: (
+            '{"routes": []}\n',  # before
+            '{"routes": [{"path": "/new/"}]}\n',  # after
+        )
+        qp = self._enqueue_cred_proxy(proposed='{"routes": [{"path": "/new/"}]}\n')
+        dashboard.approve(qp)
+        entries = read_audit_entries("cred-proxy", "dev")
+        self.assertEqual(1, len(entries))
+        self.assertIn('+{"routes": [{"path": "/new/"}]}', entries[0].diff)
+        self.assertIn('-{"routes": []}', entries[0].diff)
+
+    def test_reject_does_not_call_apply(self):
+        called = []
+        dashboard.apply_routes_change = lambda slug, content: (
+            called.append(True) or ("", content)
+        )
+        qp = self._enqueue_cred_proxy()
+        dashboard.reject(qp, reason="no thanks")
+        self.assertEqual([], called)
+        # Reject still writes a response + audit entry with empty diff.
+        resp = read_response(qp.queue_dir, qp.proposal.id)
+        self.assertEqual(STATUS_REJECTED, resp.status)
+        entries = read_audit_entries("cred-proxy", "dev")
+        self.assertEqual(1, len(entries))
+        self.assertEqual("", entries[0].diff)
+
+
 class TestEditInEditor(unittest.TestCase):
     def test_runs_editor_returns_edited_content(self):
         # Fake "editor" is /bin/sh -c 'cat <<EOF > $1 ... EOF'