#1179 Quests can be farmed by repeating the same command in a loop

Description

Quests can be trivially gamed by running the same command in a loop. Progress appears to be credited per invocation with no dedup/idempotency check, so a user can farm quest completion (and any associated XP/rewards/leaderboard standing) by repeating a single command over and over rather than actually doing distinct, meaningful work.

This undermines the point of quests as a signal of genuine usage and creates an unfair leaderboard: someone scripting while true; do <cmd>; done out-earns someone using swamp normally.

Steps to Reproduce

1. Start a quest that tracks running a given command/method.
2. Run the same command repeatedly (e.g. re-run the identical model method, or loop the same swamp invocation with no state change).
3. Observe quest progress incrementing on each repeat.
4. Complete/farm the quest purely by repetition, without doing distinct work.

Expected Behavior

Quest progress should be credited for distinct, meaningful actions, not raw command repetition. Repeated identical/no-op invocations should be deduped or rate-limited so quests can't be farmed by looping the same command.

Suggested Mitigations

• Dedup progress on identical repeated invocations (idempotency key on command + args + target/state).
• Require distinct targets or a state change to count toward progress.
• Rate-limit or debounce quest credit per command within a time window.
• Cap how much of a quest can be completed by a single repeated command.

Environment

• swamp CLI (see swamp --version)
• Reproducible via any quest that counts command/method invocations.