Enhancement: Add apc memory remove command to delete individual cache entries

[FZ2000]

Summary

There is an apc mcp remove command to delete MCP server entries from the cache, but no equivalent command for memory entries. Power users who want to clean up stale, test, or unwanted memory entries from the cache have no way to do this short of directly editing ~/.apc/cache/memory.json.

Motivation

During testing, I accumulated 195 old-format memory entries from Docker integration tests (apc memory add calls). There is no way to remove these without hand-editing JSON.

More generally, users may want to:

• Remove a specific collected memory file they no longer want synced
• Remove manually-added entries (apc memory add) that are outdated
• Clean up entries left over from tools they've uninstalled

Expected Interface

# Remove by entry ID
apc memory remove <id>

# Interactive selection (like apc mcp remove)
apc memory remove

# Remove all entries from a specific tool
apc memory remove --tool openclaw

# Clear all legacy (entry_id schema) manual entries
apc memory remove --legacy

Related

• apc mcp remove already exists and could serve as a template for this feature
• Resolves confusion from issue Bug: apc memory add uses legacy entry_id schema while apc collect uses new id/source_file schema — pollutes cache with mixed schemas #45 (mixed-schema cache) by giving users a way to clean up

Environment

• macOS Darwin 25.2.0 (arm64)
• apc version 0.1.0