refactor(rebrand): rename & rebrand CI → CIAgent across all source and test files

- Type renames: CIConfig → CIAgentConfig, DEFAULT_CI_CONFIG → DEFAULT_CIAGENT_CONFIG
- Type renames: CiMetadata → CIAgentMetadata, ParsedCiCommit → ParsedCIAgentCommit
- Function renames: initCI → initCIAgent, isCIInitialized → isCIAgentInitialized
- Function renames: extractCiBlock → extractCIAgentBlock, parseCiBlock → parseCIAgentBlock
- Class renames: CiFiles → CIAgentFiles
- Import paths: ci-files.js → ciagent-files.js
- Directory paths: .ci/ → .ciagent/ across all source and test files
- Check names: ".ci directory exists" → ".ciagent directory exists"
- Check names: "CI config valid" → "CIAgent config valid"
- Temp dir names: ci-*-test- → ciagent-*-test-
- CLI examples: "ci init" → "ciagent init"
- Fix deepMerge infinite recursion bug in config.ts
- ---ci---/---/ci--- block markers preserved unchanged
- All 31 test suites, 370 tests passing

---ci---
phase: 1
milestone: v0.5
plan: 07
task: 07-01-01
status: execute
---/ci---

src/core/git-context.ts

@@ -1,7 +1,7 @@
 import { execSync } from "node:child_process";
 import {
-  ParsedCiCommit,
-  CiMetadata,
+  ParsedCIAgentCommit,
+  CIAgentMetadata,
   CommitDecision,
 } from "../types/commit-meta.js";
 import { parseCommitMessage } from "./commit-parser.js";
@@ -16,7 +16,7 @@ export interface ProjectState {
   phasesCompleted: number[];
   phaseBranches: BranchInfo[];
   milestoneBranches: string[];
-  lastCommit: ParsedCiCommit | null;
+  lastCommit: ParsedCIAgentCommit | null;
 }
 
 export interface BranchInfo {
@@ -69,13 +69,13 @@ export class GitContext {
     return this.git("rev-parse --abbrev-ref HEAD");
   }
 
-  getRecentCommits(count: number = 20): ParsedCiCommit[] {
+  getRecentCommits(count: number = 20): ParsedCIAgentCommit[] {
     const format = "%H%x00%s%x00%B%x01";
     const raw = this.git(`log --max-count=${count} --format="${format}"`);
 
     if (!raw) return [];
 
-    const commits: ParsedCiCommit[] = [];
+    const commits: ParsedCIAgentCommit[] = [];
     const entries = raw.split("\x01").filter(Boolean);
 
     for (const entry of entries) {
@@ -93,7 +93,7 @@ export class GitContext {
     return commits;
   }
 
-  getLatestCiCommit(): ParsedCiCommit | null {
+  getLatestCiCommit(): ParsedCIAgentCommit | null {
     const commits = this.getRecentCommits(1);
     return commits.length > 0 ? commits[0] : null;
   }
@@ -207,7 +207,7 @@ export class GitContext {
     return decisions;
   }
 
-  getDecisionsFromCommits(commits: ParsedCiCommit[], phase?: number): CommitDecision[] {
+  getDecisionsFromCommits(commits: ParsedCIAgentCommit[], phase?: number): CommitDecision[] {
     const decisions: CommitDecision[] = [];
     for (const commit of commits) {
       if (commit.ci?.decisions) {
@@ -300,20 +300,20 @@ export class GitContext {
     };
   }
 
-  getCommitsForPhase(phase: number): ParsedCiCommit[] {
+  getCommitsForPhase(phase: number): ParsedCIAgentCommit[] {
     const commits = this.getRecentCommits(200);
     return commits.filter(
       (c) => c.scope === `P${String(phase).padStart(2, "0")}` || c.ci?.phase === phase
     );
   }
 
-  getCommitsForBranch(branch: string): ParsedCiCommit[] {
+  getCommitsForBranch(branch: string): ParsedCIAgentCommit[] {
     const format = "%H%x00%s%x00%B%x01";
     const raw = this.git(`log ${branch} --max-count=100 --format="${format}"`);
 
     if (!raw) return [];
 
-    const commits: ParsedCiCommit[] = [];
+    const commits: ParsedCIAgentCommit[] = [];
     const entries = raw.split("\x01").filter(Boolean);
 
     for (const entry of entries) {