Post-merge cleanup: whitespace, doc sync, canonical skill names, root CLAUDE.md (#33)

Cleanup pass following the CoCounsel merge (#4) and Lexis removal (#5):
- Normalize whitespace and JSON indentation across plugin metadata files
- Sync marketplace.json with plugin.json (ip-legal description, Courtroom5 title field)
- Add missing ai-inventory and invention-intake rows to README skill reference
- Replace stale short-form skill names in customize/cold-start SKILL.md prose with canonical directory names across 11 plugins (same bug class as the /setup -> /cold-start-interview QA fix)
- Fix FYY -> FYI typo and a phantom WebFetch claim in launch-radar docs
- Address review findings: line-wrapped /check-claims, /renewals-due -> /renewal-tracker, stale /setup in references/, agent.yaml comment contradiction, redundant 'intake intake'
- Add root CLAUDE.md with validation conventions (claude plugin validate, I1-I11 invariants, frontmatter requirements) and a marketplace.json description + $schema

No behavioral changes. claude plugin validate passes clean.

.claude-plugin/marketplace.json

@@ -1,5 +1,7 @@
 {
+  "$schema": "https://anthropic.com/claude-code/marketplace.schema.json",
   "name": "claude-for-legal",
+  "description": "Reference agents, skills, and data connectors for the legal workflows we see most — in-house commercial, privacy, product, corporate, employment, litigation, regulatory, AI governance, IP, and the learning side of the practice (law school clinics and students).",
   "owner": {
     "name": "Anthropic"
   },
@@ -95,7 +97,7 @@
     {
       "name": "ip-legal",
       "source": "./ip-legal",
-      "description": "Runs first-pass trademark clearance and freedom-to-operate triage, drafts and triages cease-and-desist letters and DMCA takedowns (send and respond), checks open source compliance, reviews IP clauses, and tracks registrations and renewal deadlines.",
+      "description": "Runs first-pass trademark clearance and freedom-to-operate triage, screens invention disclosures for initial patentability, drafts and triages cease-and-desist letters and DMCA takedowns (send and respond), checks open source compliance, reviews IP clauses, and tracks registrations and renewal deadlines.",
       "author": {
         "name": "Anthropic"
       }