fix(chat): Update FsRead toolspec, return truncated output is file is too large

[jguoamz]

Problem

• Reading a big file will use too many tokens and cause a bad UX
• fsRead will read very slow if the file is big by reading every 100 lines

Solution

• Truncating the output of fsRead if it's bigger than 200K characters
• Update fsRead toolSpec
• Set different output limit for tools as each tool is expected to handle different information and there is a trade-off on tokens vs good UX
• Improve JSON parse error handling
• Update toolResult status correctly for failed bash command

---

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[github-actions]

• This pull request implements a feat or fix, so it must include a changelog entry (unless the fix is for an unreleased feature). Review the changelog guidelines.
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[ashishrp-aws]

/retryBuilds