Add dotnet-ef JSON config defaults and validation features

[IMZihad21]

Fixes #35231

Summary

This PR adds support for loading default dotnet ef options from .config/dotnet-ef.json.

Config is discovered by walking up from the current working directory. When a matching CLI option is not provided, values from config are used.

Supported config properties:

• project
• startupProject
• framework
• configuration
• context

CLI options continue to take precedence.

Changes

• Added config discovery/loading in src/dotnet-ef/DotNetEfConfigLoader.cs.
• Updated src/dotnet-ef/RootCommand.cs to apply config defaults for root options and context forwarding behavior.
• Added resource-backed user-facing errors in:
  • src/dotnet-ef/Properties/Resources.resx
  • src/dotnet-ef/Properties/Resources.Designer.cs
• Added tests in test/dotnet-ef.Tests/DotNetEfConfigTest.cs for:
  • discovery and nearest-config behavior
  • CLI-over-config precedence
  • relative/absolute path handling
  • argument propagation
  • invalid/unreadable config handling

Config snapshot

{
  "project": "src/App.Infrastructure",
  "startupProject": "src/App.Api",
  "framework": "net9.0",
  "configuration": "Debug",
  "context": "AppDbContext"
}

Validation

• .\restore.cmd
• . .\activate.ps1
• dotnet test test/dotnet-ef.Tests/dotnet-ef.Tests.csproj

Result: passed locally.

Impact

• Reduces repeated dotnet ef arguments in repo workflows.
• Preserves existing behavior by keeping explicit CLI options authoritative.
• Improves failure diagnostics for malformed/unsupported config content.

---

Review updates

• Fixed dbcontext optimize so config-injected --context no longer changes skip-optimization behavior.
• Fixed explicit context detection to handle both = and : forms, such as --context:Foo and -c:Foo.
• Fixed config validation order so forbidden/unknown properties report the right error even when the JSON value is non-string.
• Added tests covering the new option forms, the optimize behavior, and non-string unsupported properties.

[IMZihad21]

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[Copilot]

Pull request overview

This PR adds support for loading default dotnet ef options from a repo-local JSON config file (.config/dotnet-ef.json), applying those defaults when corresponding CLI options aren’t provided, while keeping explicit CLI arguments authoritative.

Changes:

• Introduces config discovery/loading + validation via DotNetEfConfigLoader (walk-up discovery, path resolution, strict property validation).
• Applies config defaults in dotnet-ef execution flow (project/startup project/framework/configuration) and conditionally forwards a default --context for select commands.
• Adds resource-backed user-facing errors and new unit tests covering discovery/precedence/path behavior and invalid/unreadable config handling.

Reviewed changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
test/dotnet-ef.Tests/DotNetEfConfigTest.cs	Adds unit tests for config discovery, precedence, path resolution, and invalid/unreadable config scenarios.
src/dotnet-ef/RootCommand.cs	Loads config defaults and conditionally appends --context to forwarded args; adds helpers for context applicability/option detection.
src/dotnet-ef/Properties/Resources.resx	Adds new localized strings for config read/validation errors.
src/dotnet-ef/Properties/Resources.Designer.cs	Adds strongly-typed accessors for the new config error strings.
src/dotnet-ef/DotNetEfConfigLoader.cs	Implements config discovery, JSON parsing, validation, and relative path resolution.

Files not reviewed (1)

• src/dotnet-ef/Properties/Resources.Designer.cs: Language not supported

[IMZihad21]

@AndriySvyryd
@copilot

Addressed all review points in the latest update.

• dbcontext optimize now bases skip-optimization on the original user args, so a config-injected --context no longer changes that behavior.
• Explicit context detection now handles both = and : forms, including --context:... and -c:....
• Config validation now switches on property name before validating value, so forbidden/unknown properties report the correct error even for non-string JSON values.
• Added/updated tests for the new option forms, optimize behavior, and non-string unsupported properties.

Please re-check the updated changes.

[Copilot]

Pull request overview

Copilot reviewed 4 out of 5 changed files in this pull request and generated no new comments.

Files not reviewed (1)

• src/dotnet-ef/Properties/Resources.Designer.cs: Language not supported