fix(rails): exclude MimeNegotiation::InvalidType by default

[moladukes]

Closes #159.

MimeNegotiation::InvalidType is raised when a client sends a malformed Accept / Content-Type header, almost always scanner traffic. Rails maps it to a 406 via ActionDispatch::ExceptionWrapper.rescue_responses, so it's not an app bug. Same category as the already-excluded BadRequest / UnknownFormat / ParseError.

• Adds the class to default_excluded_exceptions
• Updates the generator template's docs
• Adds spec/posthog/rails/configuration_spec.rb

bundle exec rspec and bundle exec rubocop pass locally.

[greptile-apps]

Prompt To Fix All With AI

Fix the following 1 code review issue. Work through them one at a time, proposing concise fixes.

---

### Issue 1 of 1
spec/posthog/rails/configuration_spec.rb:15-27
The team's coding standard prefers parameterised tests. The two "excludes … by default" examples are identical in structure and are ideal candidates for a shared iteration. A loop-based approach also makes it trivial to extend coverage to every class in `default_excluded_exceptions` without repeating the expectation.

```suggestion
    {
      'ActionController::RoutingError' => ActionController::RoutingError.new('No route matches'),
      'ActionDispatch::Http::MimeNegotiation::InvalidType' =>
        ActionDispatch::Http::MimeNegotiation::InvalidType.new('"foo" is not a valid MIME type')
    }.each do |name, exception|
      it "excludes #{name} by default" do
        expect(config.should_capture_exception?(exception)).to be false
      end
    end
```

_{Reviews (1): Last reviewed commit: "fix(rails): exclude MimeNegotiation::Inv..." | Re-trigger Greptile}

[greptile-apps]

The team's coding standard prefers parameterised tests. The two "excludes … by default" examples are identical in structure and are ideal candidates for a shared iteration. A loop-based approach also makes it trivial to extend coverage to every class in default_excluded_exceptions without repeating the expectation.

Suggested change

	it 'excludes ActionController::RoutingError by default' do
	exception = ActionController::RoutingError.new('No route matches')
	expect(config.should_capture_exception?(exception)).to be false
	end
	it 'excludes ActionDispatch::Http::MimeNegotiation::InvalidType by default' do
	# Raised when a client sends a malformed Accept / Content-Type header
	# (typically scanner traffic). Rails maps it to a 406 — see
	# ActionDispatch::ExceptionWrapper.rescue_responses — so it is not a
	# bug worth capturing.
	exception = ActionDispatch::Http::MimeNegotiation::InvalidType.new('"foo" is not a valid MIME type')
	expect(config.should_capture_exception?(exception)).to be false
	end
	{
	'ActionController::RoutingError' => ActionController::RoutingError.new('No route matches'),
	'ActionDispatch::Http::MimeNegotiation::InvalidType' =>
	ActionDispatch::Http::MimeNegotiation::InvalidType.new('"foo" is not a valid MIME type')
	}.each do |name, exception|
	it "excludes #{name} by default" do
	expect(config.should_capture_exception?(exception)).to be false
	end
	end

Prompt To Fix With AI

This is a comment left during a code review.
Path: spec/posthog/rails/configuration_spec.rb
Line: 15-27

Comment:
The team's coding standard prefers parameterised tests. The two "excludes … by default" examples are identical in structure and are ideal candidates for a shared iteration. A loop-based approach also makes it trivial to extend coverage to every class in `default_excluded_exceptions` without repeating the expectation.

```suggestion
    {
      'ActionController::RoutingError' => ActionController::RoutingError.new('No route matches'),
      'ActionDispatch::Http::MimeNegotiation::InvalidType' =>
        ActionDispatch::Http::MimeNegotiation::InvalidType.new('"foo" is not a valid MIME type')
    }.each do |name, exception|
      it "excludes #{name} by default" do
        expect(config.should_capture_exception?(exception)).to be false
      end
    end
```

How can I resolve this? If you propose a fix, please make it concise.

Note: If this suggestion doesn't match your team's coding style, reply to this and let me know. I'll remember it for next time!

[moladukes]

Applied in a4027a9 and kept the comment about why InvalidType matters above the hash.