fix: Cleanup endowment handling of maxRequestTime

[FrederikBolding]

Several endowments had half-baked support for maxRequestTime that would then fail their getters or had validation setup but didn't allow the caveat at the permission level. This PR standardizes and allows the caveat everywhere as intended.

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Note

Medium Risk
Touches snap permission specifications and caveat getters, which can affect runtime permission validation and how endowment requests are interpreted. Changes are straightforward but broad across multiple endowments and tests.

Overview
Standardizes endowment caveat support for maxRequestTime. Updates multiple endowment permission specs (assets, cronjob, signature-insight, plus previously caveat-less page-home, page-settings, and lifecycle-hooks) to explicitly allow maxRequestTime and wire up a generic validator where missing.

Fixes caveat getters to handle multiple caveats. getCronjobCaveatJobs, getRpcCaveatOrigins, getKeyringCaveatOrigins, getSignatureOriginCaveat, and getTransactionOriginCaveat now search for the relevant caveat type instead of asserting there is exactly one caveat, with tests updated accordingly.

Updates inline snapshots in permissions and snaps-simulation to reflect the new allowed caveats/validators, and tweaks Jest coverage thresholds.

^{Written by Cursor Bugbot for commit 5fb24d5. This will update automatically on new commits. Configure here.}

[Mrtenz]

Wondering if this check (or assertion in some other endowments) is still necessary. We can maybe just rewrite to permission?.caveats?.find?.(...), right?

[FrederikBolding]

Yeah, good point!

[FrederikBolding]

For assertions, I've kept those around when the caveat is required.

[Mrtenz]

Yeah, but we assert after permission.caveats.find() in those cases as well.

[FrederikBolding]

Ah, yes, we can dedupe

[FrederikBolding]

5fb24d5

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.40%. Comparing base (413290c) to head (5fb24d5).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #3826   +/-   ##
=======================================
  Coverage   98.39%   98.40%           
=======================================
  Files         430      430           
  Lines       12454    12448    -6     
  Branches     1936     1933    -3     
=======================================
- Hits        12254    12249    -5     
+ Misses        200      199    -1     

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Cursor Bugbot has reviewed your changes and found 1 potential issue.