add resilient AnimView fallback and cache bust query param

[mmsqe]

• add AnimView fallback is to prevent Animation tab from a hard Error evaluating animation view expression: 'AnimView'. to renders a fallback message and logs debug details like nodePos, nodeText, fingerprint.
• add cache busting (__ts) is to avoid stale spec/anim fetches during local edits, so UI evaluates the latest file content instead of cached old text.
• local server query-path fix is to ensure /local_dir/*.tla?__ts=... resolves correctly by stripping query params before filesystem mapping in serve.py, while remote spec URLs are unaffected which are fetched directly by browser from remote host.

[will62794]

Can you explain the motivation behind this change more clearly? The bullet points are a bit vague to me.

[mmsqe]

Can you explain the motivation behind this change more clearly? The bullet points are a bit vague to me.

Sure @will62794, just updated the description, we encountered local specs where AnimView throws during evaluation, adding a fallback plus diagnostics should make debugging easier.