Reimplement Claude Code adapter

[codeaholicguy]

Summary

• Rewrites ClaudeCodeAdapter internals to follow the same structural patterns as CodexAdapter, process start time matching, bounded session scanning, and phased session-to-process matching
• Adds process start time matching for accurate session pairing when multiple Claude processes share the same CWD
• Replaces greedy any mode with tolerance-gated cwd -> missing-cwd -> parent-child matching phases to prevent cross-project session stealing
• Removes history.jsonl dependency — summaries extracted directly from session JSONL with command tag parsing and noise filtering
• Public API is unchanged

Key changes

Session matching (cwd -> missing-cwd -> parent-child):

• cwd/missing-cwd modes defer assignment when the best candidate is outside the 2-minute start-time tolerance, allowing parent-child mode to find a better match (e.g., worktree sessions)
• parent-child mode matches when process CWD equals, is a parent of, or is a child of session path, acts as a safety net for deferred matches
• Within tolerance, candidates are ranked by recency (most recent activity) instead of smallest time difference

Session parsing:

• sessionStart parsed from first JSONL entry, including snapshot.timestamp for file-history-snapshot entries
• Metadata entry types (last-prompt, file-history-snapshot) excluded from lastEntryType tracking
• sessions-index.json is optional, falls back to lastCwd from session content
• Breadth-first bounded scanning ensures at least one session per project directory

Process detection:

• isClaudeExecutable() checks executable basename (claude/claude.exe) instead of substring matching, prevents false positives from processes with "claude" in path arguments

Status & summary:

• No age-based IDLE override, every listed agent is backed by a running process, so entry type is the correct status indicator
• Process-only agents (no session file) show IDLE status with "Unknown" summary
• Summary extracted from last user message with <command-message> tag parsing and skill expansion ARGUMENTS extraction