Add argument-specific cache clearing

[shaypal5]

Summary

Closes #53.

Adds argument-specific cache invalidation through the existing cache-management API:

• func.clear_cache() keeps clearing all cached entries for the wrapped function.
• func.clear_cache(*args, **kwargs) now clears only the cache entry matching that call signature.
• await func.aclear_cache(*args, **kwargs) supports the same targeted behavior for async wrappers.

Implementation

• Adds a clear_cache_entry(key) core primitive plus async fallback support in _BaseCore.
• Implements targeted deletion for memory, pickle, MongoDB, Redis, SQL, and S3 backends.
• Reuses the existing argument-to-cache-key normalization so positional arguments, keyword arguments, defaults, and method self handling match normal cache lookups.
• Documents targeted clearing in README.rst.

Validation

• pytest tests/test_smoke.py::test_clear_cache_for_specific_arguments tests/test_smoke.py::test_clear_cache_for_specific_method_arguments tests/test_async_core.py::TestBasicAsyncCaching::test_clear_cache_for_specific_arguments tests/sql_tests/test_sql_core.py::test_sql_clear_cache_for_specific_arguments tests/mongo_tests/test_mongo_core.py::test_mongo_clear_cache_for_specific_arguments tests/redis_tests/test_redis_core.py::test_redis_clear_cache_for_specific_arguments tests/s3_tests/test_s3_core.py::test_s3_clear_cache_for_specific_arguments -q
• pytest -m "memory or pickle" -q
• pytest -m "sql or mongo or redis or s3" -q
• pytest tests/test_typing.py -q
• ruff check .
• git diff --check
• README parsed with docutils.core.publish_doctree

Notes

• No open repository milestone was available to assign.
• python setup.py checkdocs is not runnable in this pyproject-only checkout because there is no setup.py; collective.checkdocs also fails under the local Python 3.12 environment due to its distutils import.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.95%. Comparing base (422f890) to head (61c86fb).

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #390   +/-   ##
=======================================
  Coverage   99.95%   99.95%           
=======================================
  Files          16       16           
  Lines        2109     2179   +70     
  Branches      251      255    +4     
=======================================
+ Hits         2108     2178   +70     
  Partials        1        1           

Flag	Coverage Δ
local	66.26% <65.11%> (-0.31%)	⬇️
mongodb	39.83% <34.88%> (-0.19%)	⬇️
postgres	41.99% <40.69%> (-0.07%)	⬇️
redis	44.60% <44.18%> (+0.03%)	⬆️
s3	41.16% <37.20%> (-0.14%)	⬇️

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Files with missing lines	Coverage Δ
src/cachier/core.py	100.00% <100.00%> (ø)
src/cachier/cores/base.py	100.00% <100.00%> (ø)
src/cachier/cores/memory.py	100.00% <100.00%> (ø)
src/cachier/cores/mongo.py	100.00% <100.00%> (ø)
src/cachier/cores/pickle.py	99.66% <100.00%> (+0.01%)	⬆️
src/cachier/cores/redis.py	100.00% <100.00%> (ø)
src/cachier/cores/s3.py	100.00% <100.00%> (ø)
src/cachier/cores/sql.py	100.00% <100.00%> (ø)

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[Copilot]

Pull request overview

Adds argument-specific cache invalidation to Cachier’s cache-management API, enabling callers to clear a single cached entry by providing the same call signature used to compute it (sync and async), across all supported backends.

Changes:

• Extend clear_cache() / aclear_cache() to accept *args, **kwargs and clear only the matching cache entry when provided.
• Introduce a core-level primitive clear_cache_entry(key) with an async-compatible aclear_cache_entry(key) default.
• Add backend implementations and tests (smoke, async, and per-backend) plus README documentation.

Reviewed changes

Copilot reviewed 16 out of 16 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
tests/test_smoke.py	Adds smoke coverage for argument-specific cache clearing (function + method).
tests/test_base_core.py	Extends base-core test double and verifies aclear_cache_entry fallback.
tests/test_async_core.py	Adds async wrapper coverage for targeted cache clearing via aclear_cache.
tests/sql_tests/test_sql_core.py	Adds SQL backend test for clearing a single cache entry by args.
tests/s3_tests/test_s3_core.py	Adds S3 backend test for clearing a single cache entry by args.
tests/redis_tests/test_redis_core.py	Adds Redis backend test for clearing a single cache entry by args.
tests/mongo_tests/test_mongo_core.py	Adds Mongo backend test for clearing a single cache entry by args.
src/cachier/cores/sql.py	Implements SQL clear_cache_entry / aclear_cache_entry deletion by key.
src/cachier/cores/s3.py	Implements S3 clear_cache_entry deletion by object key.
src/cachier/cores/redis.py	Implements Redis clear_cache_entry / aclear_cache_entry deletion by key.
src/cachier/cores/pickle.py	Implements pickle clear_cache_entry, including separate-files mode deletion.
src/cachier/cores/mongo.py	Implements Mongo clear_cache_entry / aclear_cache_entry deletion by key.
src/cachier/cores/memory.py	Implements memory clear_cache_entry removal by key.
src/cachier/cores/base.py	Adds abstract clear_cache_entry plus async-thread fallback aclear_cache_entry.
src/cachier/core.py	Extends public clear_cache/aclear_cache wrappers to support argument-specific clearing.
README.rst	Documents targeted cache clearing usage for sync and async helpers.