fix(declare-program): handle numeric instruction suffixes

[abhinavgautam01]

Fixes #4281

Summary

Fixes declare_program! account module re-exports for instruction names that contain an underscore before a numeric suffix, such as initialize_with_token_2022.

Previously, generated internal account modules normalized the instruction name through CamelCase and then snake_case, while the public client/CPI account re-exports used the raw IDL instruction name. That could make the re-export look for __cpi_client_accounts_initialize_with_token_2022 even though the generated module was named __cpi_client_accounts_initialize_with_token2022.

Changes

• Normalize declare_program! client/CPI account re-export module names the same way as generated account modules.
• Add a regression test for initialize_with_token_2022.
• Add the matching instruction to the declare-program fixture IDL.

Testing

• cargo +nightly fmt --check -p anchor-attribute-program
• cargo test -p anchor-attribute-program test_gen_accounts_mod_name_matches_generated_accounts
• cargo check -p declare-program --features cpi
• cargo check -p external
• cargo clippy -p anchor-attribute-program --all-targets -- -D warnings
• git diff --check

Note: full workspace cargo +nightly fmt --check currently fails on an unrelated pre-existing import ordering diff in lang/src/lib.rs, which this PR does not touch...