Move `bump_persistent` read bumps out of `get_*` into a dedicated `bump_*_view` set

[P3az3]

Problem Statement

Every get_* in campaign/src/storage.rs calls bump_persistent, refreshing the TTL of the loaded entry on every call. This is desirable for frequently-updated campaign state but expensive for views called often by dashboards/UI.

For dashboard viewers, refreshing TTL on every poll pushes the eventual archival further out, but each refresh costs a host invocation. For light-traffic view-only callers (analytics pages that refresh every few seconds), the work is unnecessary.

Expected Outcome

Split reads into:

• get_* — read-only, no TTL bump (cheap).
• get_*_bumped — read + bump (for state-touching callers).

Update donate, claim_refund, release_milestone*, etc. to explicitly use _bumped reads. Views (analytics, dashboard) use plain get_*.

Acceptance Criteria

• All #[contractimpl] analytics views (get_campaign_report, get_dashboard_metrics, etc.) use get_* (non-bumping).
• All mutating paths (donate, claim_refund, release_*, etc.) use get_*_bumped.
• A new test test_view_does_not_bump_ttl asserts a view call does not bump the TTL.

Implementation Notes

• Refactor bump_persistent to remain internal (fn rather than pub fn).
• Add JSDoc-style comments on which path each name belongs to.

Affected Files / Modules

• campaign/src/storage.rs
• campaign/src/lib.rs (entrypoint usage)
• campaign/src/views.rs

Dependencies — None.