feat(kyberforge): enable codex marketplace output

Uncomment marketplace.outputs.codex in apm.yml. Codex output requires
every package to declare a category -- added one per package (Developer
Tools / Utilities / Version Control / Productivity, matching each
plugin's actual scope).

Re-running apm pack after enabling codex auto-synced 'codex' into each
local package's own targets: list (apm.yml, per plugin) -- packages
belonging to a marketplace that publishes a codex output need to declare
codex as a supported compile target for that to be coherent. Verified
idempotent: a second apm pack --check-clean run makes no further changes.

.claude-plugin/marketplace.json regenerated (now carries category per
plugin); .agents/plugins/marketplace.json is the new codex artifact.

Refs: #90

plugins/bin/apm.yml

@@ -15,8 +15,10 @@ type: skill
 # Resolution order: --target flag > this field > auto-detect from filesystem.
 # Accepted values: agent-skills, antigravity, claude, codex, copilot, cursor, gemini, grok-build, kiro, opencode, windsurf
 targets:
-- claude
-- copilot
+  - claude
+  - copilot
+  - codex
+
 dependencies:
   apm: []
   mcp: []

plugins/core/apm.yml

@@ -19,6 +19,7 @@ type: skill
 targets:
   - claude
   - copilot
+  - codex
 
 # "auto" publishes the authoritative local source layout, or list explicit
 # repo paths to define the complete publication set.

plugins/git/apm.yml

@@ -17,6 +17,7 @@ keywords:
 targets:
   - claude
   - copilot
+  - codex
 type: hybrid
 
 dependencies:

plugins/gitea/apm.yml

@@ -20,6 +20,7 @@ type: hybrid
 targets:
   - claude
   - copilot
+  - codex
 
 # "auto" publishes the authoritative local source layout, or list explicit
 # repo paths to define the complete publication set.

plugins/kyberforge/apm.yml

@@ -14,6 +14,7 @@ type: hybrid
 targets:
   - claude
   - copilot
+  - codex
 
 # "auto" publishes the authoritative local source layout — the large
 # docs/research/ tree stays as root-level passthrough content, not a primitive.

plugins/lint/apm.yml

@@ -19,8 +19,9 @@ type: hybrid
 # Resolution order: --target flag > this field > auto-detect from filesystem.
 # Accepted values: agent-skills, antigravity, claude, codex, copilot, cursor, gemini, grok-build, kiro, opencode, windsurf
 targets:
-- claude
-- copilot
+  - claude
+  - copilot
+  - codex
 dependencies:
   apm: []
   mcp: []