feat: add .env inheritance support in Envied and EnviedGenerator

[techouse]

This pull request introduces support for environment file inheritance in the Envied package, allowing users to specify multiple .env files whose values are loaded and merged in order. The changes include updates to the Envied annotation, enhancements to the environment loading logic, and comprehensive tests and documentation to cover the new feature.

Environment inheritance feature:

• Added a new inheritFrom parameter to the Envied annotation, allowing users to specify an ordered list of .env files to be loaded before the primary file, with later files overriding earlier values. (packages/envied/lib/src/envied_base.dart, packages/envied_generator/lib/src/generator.dart) [1] [2] [3] [4] [5] [6] [7]

• Updated the environment variable loading logic to support merging values from multiple files, preserving the correct override order and supporting variable interpolation across inherited files. (packages/envied_generator/lib/src/load_envs.dart, packages/envied_generator/lib/src/parser.dart) [1] [2] [3]

Documentation improvements:

• Extended the README with a new section and example for environment inheritance, explaining usage and override behavior. (packages/envied/README.md) [1] [2]

Testing and validation:

• Added new and updated tests to verify the behavior of the inheritFrom parameter, including edge cases with missing files and multiple inheritance scenarios. (packages/envied/test/envy_test.dart, packages/envied_generator/test/envy_generator_test.dart, packages/envied_generator/test/src/generator_tests_with_inheritance.dart, and new test .env files) [1] [2] [3] [4] [5] [6] [7] [8] [9]

Minor improvements:

• Improved handling of empty path values in the Envied annotation to default to .env. (packages/envied/lib/src/envied_base.dart, packages/envied_generator/lib/src/generator.dart, packages/envied_generator/test/src/generator_tests.dart) [1] [2]

Changelog update:

• Updated the changelog to reflect the addition of the environment inheritance feature. (CHANGELOG.md)

[Copilot]

Pull request overview

Adds .env inheritance to Envied so consumers can define shared defaults in one or more base files and override them in environment-specific files, with generator support to load/merge/interpolate across the chain.

Changes:

• Added inheritFrom to the Envied annotation and documented inheritance behavior.
• Updated env loading/parsing in envied_generator to merge multiple files (in order) while keeping “first duplicate wins” within a single file.
• Added generator tests + new fixture .env files covering override, interpolation, duplicates, and missing inherited files.

Reviewed changes

Copilot reviewed 14 out of 15 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
packages/envied/test/envy_test.dart	Adds unit tests for the new inheritFrom default/assignment behavior.
packages/envied/README.md	Documents “Environment inheritance” and clarifies interaction with build path override.
packages/envied/lib/src/envied_base.dart	Introduces inheritFrom on Envied annotation.
packages/envied_generator/lib/src/parser.dart	Extends parsing to support interpolation using an externally-supplied env map (for inherited values).
packages/envied_generator/lib/src/load_envs.dart	Adds loadEnvsFromPaths to load/merge envs from multiple files in order.
packages/envied_generator/lib/src/generator.dart	Wires inheritFrom into generation, updates generated_from comment to include all contributing files.
packages/envied_generator/test/envy_generator_test.dart	Registers the new inheritance-focused generator test suite.
packages/envied_generator/test/src/generator_tests_with_inheritance.dart	Adds source_gen_test coverage for inheritance scenarios (overrides, interpolation, missing files, multi-annotation).
packages/envied_generator/test/.env.inheritance_defaults	Inheritance fixture: base defaults.
packages/envied_generator/test/.env.inheritance_middle	Inheritance fixture: mid-layer overrides.
packages/envied_generator/test/.env.inheritance_child	Inheritance fixture: child overrides + interpolation + duplicates.
packages/envied_generator/test/.env.inheritance_alt_defaults	Inheritance fixture: alternate defaults for multi-annotation test.
packages/envied_generator/test/.env.inheritance_alt_child	Inheritance fixture: alternate child overrides for multi-annotation test.
CHANGELOG.md	Trims trailing whitespace (no functional/log entry change).
.gitignore	Ignores .history and .DS_Store.

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[Copilot]

Pull request overview

Copilot reviewed 16 out of 17 changed files in this pull request and generated 2 comments.

Comments suppressed due to low confidence (1)

CHANGELOG.md:484

• PR description mentions a changelog entry for the new environment inheritance feature, but this change only removes a trailing blank line. If the feature is intended to be released, please add an explicit changelog bullet under the appropriate package/version section.

 - **FIX**(envied_generator): build extensions setting (#30).
 - **FIX**: CI workflow and dependency updates (#31).

[Copilot]

Pull request overview

Copilot reviewed 15 out of 16 changed files in this pull request and generated 2 comments.

[techouse]

@petercinibulk this should be ready for review now :)