Limitcast 0.18.0: hold duplicate spawns and cap fat tool calls

The guard holds a second subagent of the same type and prompt while the first is still running. install --alerts caps a fat Read, Grep, or MCP call before it runs. report --jobs names the startup piece that changed between two runs of a job. A large Claude session is announced after 5 idle minutes; the hold stays at 60.

• The guard holds a second subagent of the same type and prompt while the first is still running in that session. Claude's stop hook clears it. A record older than 30 minutes is dropped, so a missed stop cannot hold the prompt all day. LIMITCAST_ALLOW=1 still spawns.
• install --alerts adds a PreToolUse check. After report --why or report --jobs, a tool whose results averaged at least 5k tokens over 3 or more calls is held when the call sets no limit (Read, Grep, and MCP tools), or its limit is lowered when it is above the cap (400 lines for Read, 100 for MCP). Bash and WebFetch are left alone. Re-run install --alerts to add the hook.
• report --jobs names the startup piece that changed between the earliest and latest run of a job, when both runs recorded one.
• After 5 idle minutes (LIMITCAST_CACHE_NOTICE_MINUTES) a large session's next message is announced and still sent. The hold stays at 60 minutes (LIMITCAST_CACHE_MINUTES).
• trim --share keeps configuration names and paths private when no measured startup transcript is available, and honors totals-only output for Codex and Grok. Sharing cannot be combined with keep-list edits, apply, or undo.

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