docs(prd): assign PRD number 0082

CI (prd-number-check) rejects unnumbered prd-new-*.md on merge to main.
Rename docs/prds/prd-new-trusted-agent-forge-identity.md to
0082-trusted-agent-forge-identity.md (0081 is claimed by #517/#519) and
update the in-repo 'PRD prd-new-trusted-agent-forge-identity' citations to
'PRD 0082'.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

tests/unit/test_manifest_md_load.py

@@ -111,7 +111,7 @@ class TestAgentFileParses(_ResolveCase):
 
 
 class TestCwdAgentIgnoredHomeWins(_ResolveCase):
-    """SC #3 (revised, PRD prd-new-trusted-agent-forge-identity): agents
+    """SC #3 (revised, PRD 0082): agents
     are home-only. A cwd agent file with the same name as a home agent no
     longer wins — it is warned-and-ignored, so the HOME agent's prompt is
     used and the home bottle stays intact."""
@@ -141,7 +141,7 @@ class TestCwdAgentIgnoredHomeWins(_ResolveCase):
 class TestCwdBottlesIgnored(_ResolveCase):
     """SC #4: a bottles/ dir under $CWD is ignored (with a warn).
     The home bottle still wins. Under
-    PRD prd-new-trusted-agent-forge-identity a cwd agents/ dir is also
+    PRD 0082 a cwd agents/ dir is also
     ignored, so $CWD contributes nothing — the filesystem layout is the
     trust boundary."""