fix: resolve spec paths relative to package install dir

The get_spec_dict function used a relative path (farialimer/specs/{provider})
which only works when the CWD contains the farialimer source tree. When
farialimer is installed as a package and imported from another project,
os.walk finds nothing and returns an empty dict, breaking all parsers
and generators.

Fix: resolve the specs directory relative to __file__ so it works
regardless of the caller's working directory.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: lmeilibr

farialimer/utils/spec_loader.py

@@ -23,7 +23,8 @@ def get_spec_dict(provider):
     value: spec yaml filepath
     """
     spec_dict = {}
-    for dirpath, _, filenames in walk(f"farialimer/specs/{provider}"):
+    _package_dir = os.path.dirname(os.path.dirname(__file__))
+    for dirpath, _, filenames in walk(os.path.join(_package_dir, "specs", provider)):
         for filename in filenames:
             if filename.endswith("yaml"):
                 spec_key = filename.split(".")[0]