fix: Ensure tags values are strings

[szokeasaurusrex]

Tag value handling was updated to ensure compliance with the Sentry spec.

• In sentry_sdk/scope.py, Scope.set_tag() was modified to convert values using safe_str(value). Scope.set_tags() was refactored to iterate and call self.set_tag() for each item, ensuring consistent conversion.
• In sentry_sdk/tracing.py, Span.set_tag() was updated to use safe_str(value).

Comprehensive tests were added:

• In tests/test_scope.py, new tests cover Scope.set_tag() and Scope.set_tags() conversion and error handling.
• A new file, tests/tracing/test_span_tags.py, was created to test Span and Transaction tag conversion.
• In tests/test_api.py, tests were added for API-level set_tag() and set_tags().

These changes ensure all tag values are strings, meeting Sentry spec requirements and improving compatibility with external tools like Sentry CLI.

Fixes #4391

[codecov]

❌ 327 Tests Failed:

Tests completed	Failed	Passed	Skipped
24929	327	24602	5790

View the top 3 failed test(s) by shortest run time

tests.test_scope::test_with_use_isolation_scope_data

Stack Traces | 0.001s run time

tests/test_scope.py:513: in test_with_use_isolation_scope_data
    assert isolation_scope_in._tags == {"before_custom_isolation_scope": 1}
E   AssertionError: assert {'before_custom_isolation_scope': '1'} == {'before_custom_isolation_scope': 1}
E     
E     Differing items:
E     {'before_custom_isolation_scope': '1'} != {'before_custom_isolation_scope': 1}
E     
E     Full diff:
E       {
E     -     'before_custom_isolation_scope': 1,
E     +     'before_custom_isolation_scope': '1',
E     ?                                      + +
E       }

tests.test_scope::test_with_use_scope_data

Stack Traces | 0.001s run time

tests/test_scope.py:708: in test_with_use_scope_data
    assert isolation_scope_in._tags == {"before_isolation_scope": 1}
E   AssertionError: assert {'before_isolation_scope': '1'} == {'before_isolation_scope': 1}
E     Differing items:
E     {'before_isolation_scope': '1'} != {'before_isolation_scope': 1}
E     Full diff:
E     - {'before_isolation_scope': 1}
E     + {'before_isolation_scope': '1'}
E     ?                            + +

tests.test_scope::test_with_use_scope_data

Stack Traces | 0.001s run time

tests/test_scope.py:708: in test_with_use_scope_data
    assert isolation_scope_in._tags == {"before_isolation_scope": 1}
E   AssertionError: assert {'before_isolation_scope': '1'} == {'before_isolation_scope': 1}
E     
E     Differing items:
E     {'before_isolation_scope': '1'} != {'before_isolation_scope': 1}
E     
E     Full diff:
E       {
E     -     'before_isolation_scope': 1,
E     +     'before_isolation_scope': '1',
E     ?                               + +
E       }

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[szokeasaurusrex]

Looks like tests are failing because the non-string values were being asserted in the test suites