docs(rebrand): rename & rebrand CI → CIAgent across all documentation, templates, and scripts

- README.md: title, project name, CLI commands, .ci/ → .ciagent/, ci-files → ciagent-files, CI Modification → CIAgent Modification
- AGENTS.md: title, project name, architecture tree, agent count (18→19), test count (25→31 suites, 218→370 tests), version (0.4.0→0.6.0), ci-files → ciagent-files, CIConfig → CIAgentConfig, CiMetadata → CIAgentMetadata, .ci/ → .ciagent/
- templates/DECISIONS.md: .ci/audit/ → .ciagent/audit/, ci audit → ciagent audit
- scripts/postinstall.js: CI postinstall → CIAgent postinstall
- scripts/install.sh: CI → CIAgent, ci-init → ciagent-init, INSTALL COMPLETE banner
- opencode/ci/workflows/*.md (11 files): .ci/ → .ciagent/, CI → CIAgent project name, ci-command → ciagent-command usage lines
- opencode/ci/references/*.md (5 files): .ci/ → .ciagent/, CI → CIAgent project name, ci-files → ciagent-files references
- opencode/ci/contexts/*.md (3 files): .ci/ → .ciagent/, CI → CIAgent project name
- opencode/agents/ci-*.md (18 files): .ci/ → .ciagent/, CI → CIAgent project name
- opencode/command/ci-*.md (11 files): CI → CIAgent project name

Preserved: ---ci---/---/ci--- markers, opencode/ci/ dir paths, ci-*.md filenames, ci listProjects()/ci setActiveProject() API names, repo URLs

---ci---
phase: 1
milestone: v0.6
plan: 01-01
task: 01-01-01
status: execute
---/ci---

opencode/agents/ci-ideation-agent.md

@@ -1,5 +1,5 @@
 ---
-description: Generates codebase-grounded improvement ideas through a specific thinking frame for CI. Uses git history to understand the codebase evolution.
+description: Generates codebase-grounded improvement ideas through a specific thinking frame for CIAgent. Uses git history to understand the codebase evolution.
 color: "#FFD700"
 tools:
   read: true
@@ -9,7 +9,7 @@ tools:
 ---
 
 <role>
-You are a CI ideation agent. You generate codebase-grounded improvement ideas through a specific thinking frame. You use git history to understand the codebase evolution and identify improvement opportunities.
+You are a CIAgent ideation agent. You generate codebase-grounded improvement ideas through a specific thinking frame. You use git history to understand the codebase evolution and identify improvement opportunities.
 
 You do not implement changes. You produce ideas with rationale for the orchestrator to evaluate and potentially plan.
 
@@ -18,11 +18,11 @@ If the prompt contains a `<files_to_read>` block, you MUST use the Read tool to
 </role>
 
 <project_context>
-If .ci/config.json has projects[] with length > 0, you are in multi-project mode.
-- Read active_project from .ci/config.json
+If .ciagent/config.json has projects[] with length > 0, you are in multi-project mode.
+- Read active_project from .ciagent/config.json
 - All commits must include `project: <active_project>` in ---ci--- block
 - Branch names are prefixed with <slug>/ in multi-project mode
-- .ci/ files are in .ci/<slug>/ subdirectories
+- .ciagent/ files are in .ciagent/<slug>/ subdirectories
 If single-project mode (projects[] empty or absent), use existing conventions.
 
 Before ideating, load context from git first:
@@ -31,15 +31,15 @@ Before ideating, load context from git first:
 2. Use GitContext.getDecisions() for existing decisions
 3. Use GitContext.getCompounds() for compound learnings
 4. Use GitContext.getLessons() for lessons that suggest improvements
-5. Read `.ci/ARCHITECTURE.md` for component boundaries
-6. Read `.ci/REQUIREMENTS.md` for incomplete requirements
+5. Read `.ciagent/ARCHITECTURE.md` for component boundaries
+6. Read `.ciagent/REQUIREMENTS.md` for incomplete requirements
 </project_context>
 
 <execution_flow>
 
 ## Step 1: Load Context
 
-Read git history and .ci/ files. Understand the codebase's current state and evolution.
+Read git history and .ciagent/ files. Understand the codebase's current state and evolution.
 
 ## Step 2: Apply Thinking Frame