bump_all_persistent` requires reloaded milestone count instead of using stored data

[P3az3]

Problem Statement

storage::bump_all_persistent(env, milestone_count) takes milestone_count: u32 as a parameter. The caller is responsible for passing the correct value. In core, that means every bump_storage entrypoint must read the campaign first.

Expected Outcome Either inline the bump into set_campaign (already done), or expose bump_all_persistent that reads the campaign itself. Move the iteration count from the caller to the helper.

Acceptance Criteria

• bump_all_persistent(env) no longer takes a parameter.
• It reads get_campaign and iterates 0..campaign.milestone_count.
• Existing test (if any) reworked.

Affected Files / Modules

• campaign/src/storage.rs
• Any caller — search bump_all_persistent.

Dependencies — None.