chore: retire the Everything Claude Code name, ECC only (#3330)

* chore: retire the Everything Claude Code name, ECC only

Replace the expanded product name and the everything-claude-code slug
with ECC across READMEs, translated docs, harness folders, skills,
commands, scripts and examples. Repo URLs now point at affaan-m/ECC.

Rename repo-internal artifacts to ecc forms (ecc-conventions skill,
ecc-guardrails, ecc-research-playbook, ecc-team-config, ecc-instincts
with ecc-* ids) and update .claude/ecc-tools.json.

Legacy install ids, plugin dirs, package names and MCP prefixes stay
where existing installs resolve against them. The codex global-state
check and harness-audit repo detection accept the new name first and
the legacy one as a fallback. The Discord bot prefers ~/GitHub/ECC and
falls back to the nested legacy checkout path.

Refresh the skill-triggers registryDigest for the changed skill text.

* fix(ecc-tools): drop managed paths to the removed Claude repo skill

.claude/skills/<repo-skill>/SKILL.md was deleted in #2770 but stayed listed in
ecc-tools.json and the team config. Remove those entries and point the Claude
Code adapter at the existing .agents/skills/ecc-conventions/SKILL.md.

.agents/skills/ecc-conventions/SKILL.md

@@ -1,16 +1,16 @@
 ---
-name: everything-claude-code
-description: Development conventions and patterns for everything-claude-code. JavaScript project with conventional commits.
+name: ecc-conventions
+description: Development conventions and patterns for ECC. JavaScript project with conventional commits.
 license: MIT
 ---
 
-# Everything Claude Code Conventions
+# ECC Conventions
 
-> Generated from [affaan-m/everything-claude-code](https://github.com/affaan-m/everything-claude-code) on 2026-03-20
+> Generated from [affaan-m/ECC](https://github.com/affaan-m/ECC) on 2026-03-20
 
 ## Overview
 
-This skill teaches Claude the development patterns and conventions used in everything-claude-code.
+This skill teaches Claude the development patterns and conventions used in ECC.
 
 ## Tech Stack
 

.agents/skills/ecc-conventions/agents/openai.yaml

@@ -0,0 +1,7 @@
+interface:
+  display_name: "ECC"
+  short_description: "Repo workflows and conventions for ECC"
+  brand_color: "#0EA5E9"
+  default_prompt: "Use $ecc-conventions to follow this repository's conventions and workflows."
+policy:
+  allow_implicit_invocation: true

.agents/skills/everything-claude-code/agents/openai.yaml

@@ -1,7 +0,0 @@
-interface:
-  display_name: "Everything Claude Code"
-  short_description: "Repo workflows for everything-claude-code"
-  brand_color: "#0EA5E9"
-  default_prompt: "Use $everything-claude-code to follow this repository's conventions and workflows."
-policy:
-  allow_implicit_invocation: true