fix: add android elf build ids

[ovitrif]

Fixes #121

Implements the Paykit producer portion of synonymdev/bitkit-android#1105.

Companion PRs:

• fix: add android elf build ids synonymdev/ldk-node#98
• fix: add android elf build ids synonymdev/bitkit-core#131
• fix: add android elf build ids synonymdev/vss-rust-client-ffi#19
• fix: integrate android elf build-id releases synonymdev/bitkit-android#1106

Summary

• adds -Wl,--build-id=sha1 to the Android linker flags for all four published targets while preserving the existing linker flags
• prepares the 0.1.0-rc40 release with refreshed Android and Swift artifacts

Protocol impact

None.

Downstream bindings

Android and Swift release artifacts are refreshed at 0.1.0-rc40. synonymdev/bitkit-android#1106 will adopt the released Paykit coordinate before merge.

Checklist

• cargo fmt --all -- --check
• cargo clippy --workspace --all-targets --all-features --locked -- -D warnings
• cargo test --workspace --all-features --locked
• RUSTDOCFLAGS="-D warnings" cargo doc --workspace --no-deps --all-features --locked
• The all-platform release build completed for iOS and Android; Android publication used isolated Maven and Gradle state
• Package metadata is consistently versioned 0.1.0-rc40
• Platform release artifacts are refreshed
• Two exact-head review passes completed with no actionable findings

Release

• Release 0.1.0-rc40

Review

• One review is enough, there's similar work that was already done in the other rust-sources repos which was already approved.