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>

docs/prds/0011-per-file-md-manifest.md

@@ -4,7 +4,7 @@
 - **Author:** didericis
 - **Created:** 2026-05-24
 
-> **Superseded in part by PRD prd-new-trusted-agent-forge-identity.**
+> **Superseded in part by PRD 0082.**
 > The `$CWD/.bot-bottle/agents/<name>.md` discovery/override path described
 > below is removed: agents are now **home-only**, like bottles. Once an agent
 > definition can select a host identity (`author`) and a host forge secret

docs/prds/0082-trusted-agent-forge-identity.md

@@ -1,4 +1,4 @@
-# PRD prd-new: Trusted agent forge identity and guidance
+# PRD 0082: Trusted agent forge identity and guidance
 
 - **Status:** Accepted
 - **Author:** didericis-claude