Fix uninlined_format_args clippy lint

[PeterXMR]

Closes #1199.

Inlines format-string arguments throughout the crate so cargo clippy -W clippy::uninlined_format_args passes, and removes the crate-wide [lints.clippy] uninlined_format_args = \"allow\" block in Cargo.toml.

How it was produced

The bulk was generated mechanically:

cargo clippy --fix --allow-dirty --all-targets -- -W clippy::uninlined_format_args

This rewrites every format!(\"... {}\", x) (and its eprintln! / info! / write! cousins) into the inlined format!(\"... {x}\") form. clippy's autofix is conservative — it skips a handful of sites with method-call arguments or shadowed identifiers — but in this codebase it covered every site in 14 files. Two additional single-line sites in src/index.rs and src/signals.rs that the fix log did not announce but the autofix did rewrite are included.

Followed by a cargo fmt --all pass to normalise the line wrapping that the rewrite occasionally collapsed.

Behaviour change

None. The inlined format!(\"... {x}\") form produces byte-identical output to the previous format!(\"... {}\", x). This is a purely syntactic refactor.

Tests

No new tests are needed for a syntactic refactor — the existing test suite is the regression check, since several tests assert on formatted output:

Test	Asserts on …
config::tests::test_auth_debug	SensitiveAuth's Debug output (goes through inlined write!)
electrum::tests::test_requests / test_version	request/response JSON whose error paths use inlined format!
status::tests::test_txinfo_json	transaction-info JSON formatting
types::tests::test_scripthash_serde	scripthash hex formatting

All 21 lib tests pass on every CI matrix configuration:

• cargo test --locked --no-default-features --all ✅
• cargo test --locked --all ✅
• cargo test --locked --features metrics_process --all ✅ (on Linux — prometheus::process_collector is target_os = \"linux\"-gated, so this config can't build on macOS regardless of the refactor; CI runs on ubuntu-latest)

Plus a focused integration smoke test against Bitcoin Core 31 on regtest, exercising every RPC code path through the Electrum protocol (relayfee, estimatefee, transaction.get hex+verbose, mempool fee_histogram, broadcast of a fresh signed tx) — all clean.

Notes for review

• Generated configure_me_config.rs in OUT_DIR has its own uninlined_format_args hits from configure_me_codegen's output. They don't trigger CI's cargo clippy -- -D warnings because the lint is allow-by-default at clippy's level (it's a pedantic-group lint). If you'd like to enforce going forward — i.e., promote the lint to warn in [lints.clippy] and rely on -D warnings to deny it — I'd need to also add #![allow(clippy::uninlined_format_args)] to the mod internal { ... } block in src/config.rs so the generated code stays quiet. Happy to do that as a follow-up, or to bundle it here if you prefer; I left it out because the issue's literal scope is just "fix the lint" rather than "enforce going forward".
• This PR is independent of Drop archived bitcoincore-rpc dependency #1288 (drop bitcoincore-rpc) — the diffs don't overlap on any line. They will rebase against each other cleanly in either order.