Fix filter equality against int literal truncating float values (#227)

[youdie006]

Fixes #227.

Problem

An extended filter comparing against an integer literal wrongly matched float values. For example $[?(@.v = 0)] matched an element with v = 0.6:

from jsonpath_ng.ext import parse
data = [{"k": "A", "v": 0.0}, {"k": "B", "v": 0.6}, {"k": "C", "v": 0}]
parse("$[?(@.v = 0)].k").find(data)   # returned ["A", "B", "C"], expected ["A", "C"]

Root cause

In Expression.find (jsonpath_ng/ext/filter.py), when the RHS literal is an int, the LHS value was coerced with int(value) before comparison. For a float LHS this truncates (int(0.6) == 0), so an equality filter against 0 wrongly matched 0.6.

Fix

Restrict the coercion to string LHS values (isinstance(value, str)). This preserves the original string->int intent (e.g. matching "5" against 5) while leaving numeric values uncoerced, so float comparisons stay exact. Booleans are unaffected (type(True) is int is False).

Tests

• Added a parametrized case issue-227-int-no-float-truncation.
• Red/green verified: without the fix the case returns ["A", "B", "C"] (fails); with the fix it returns ["A", "C"].
• Full ext suite and tests/ pass (352 passed).
• CHANGELOG.md updated under [Unreleased] / Fixed per CONTRIBUTING.md.

Thanks to @AkiraVoid for the clear bug report.

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This change was prepared with AI assistance and reviewed by me before submission.