Consider caching for shellStartup profiles

[anthonykim1]

Clear profile modification when:

• user explicitly mention Revert shell startup clear changes
• user switches from shellStartup to command(?)

If they stay in shellStartup, we should not clear profile file, since shell integration activation time will vary depending on their device shell, setup.

• We clear out profile file modification when we detect shell integration kicks in, we should be less aggressive about this.