chore(solana): use shared cache utils

[taran-a]

Explanation

Migrates the Solana snap to the shared caching utilities in @metamask/snap-networks-utils and removes its local copies (src/core/caching/).

Behavioral changes:

• Cache keys for fetchJsonParsedAccount and fetchMint are now built from only the result-affecting, serializable config parts (commitment and minContextSlot) instead of the whole FetchAccountConfig object. Previously abortSignal ended up in the cache key (making it both unstable and non-serializable); it is now excluded from the key and not forwarded to the cached fetch, since it only affects cancellation. Keys are therefore more stable (more cache hits for equivalent requests).
• Both cached wrappers now call the SDK function directly with an explicitly-deconstructed config rather than wrapping an internal closure, and the SDK's account result types (not statically Serializable) are asserted cache-safe via an intersection with Serializable.
• Error logging: shared useCache takes an optional logger (default silent); call sites pass the snap logger to preserve current output.

References

• Related to WPN-1635

Checklist

• I've updated the test suite for new or updated code as appropriate
• I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
• I've communicated my changes to consumers by updating changelogs for packages I've changed
• I've introduced breaking changes in this PR and have prepared draft pull requests for clients and consumer packages to resolve them

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud