fix(gradle-plugin): add .convention() defaults to Property<T> fields in ResolveTask

[lfgcampos]

Pull Request

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Closes #5136

Description

In Gradle 9, calling Property<T>.get() on a property that has neither a set value nor a convention throws at runtime:

Cannot query the value of task property '...' because it has no value available.

ResolveTask.resolve() calls .get() unconditionally on prettyPrint, readAllResources, sortOutput, alwaysResolveAppPath, skipResolveAppPath, and encoding. None had a .convention(...) default, so they throw when not explicitly set by the caller.

Fix: add .convention(false) to the five boolean fields and .convention(StandardCharsets.UTF_8.name()) to encoding. Callers that set these explicitly are unaffected.

Property	Type	Convention	Notes
outputFileName	Property<String>	"openapi"	Was unguarded .get()
outputFormat	Property<Format>	Format.JSON	Was unguarded .get()
prettyPrint	Property<Boolean>	false	Matches SwaggerPlugin
readAllResources	Property<Boolean>	false	Matches SwaggerPlugin
encoding	Property<String>	Charset.defaultCharset().name()	Matches SwaggerPlugin
sortOutput	Property<Boolean>	false	Matches SwaggerPlugin
alwaysResolveAppPath	Property<Boolean>	false	Matches SwaggerPlugin
skipResolveAppPath	Property<Boolean>	false	Matches SwaggerPlugin
skip	Property<Boolean>	false	Already safe via .getOrElse(), added for consistency
openAPI31	Property<Boolean>	false	Matches SwaggerPlugin
convertToOpenAPI31	Property<Boolean>	false	Fixes latent bug: .get() at line 578 had no isPresent() guard

Type of Change

• 🐛 Bug fix
• ✨ New feature
• ♻️ Refactor (non-breaking change)
• 🧪 Tests
• 📝 Documentation
• 🧹 Chore (build or tooling)

Checklist

• I have added/updated tests as needed
• I have added/updated documentation where applicable
• The PR title is descriptive
• The code builds and passes tests locally
• I have linked related issues (if any)

Screenshots / Additional Context

[ewaostrowska]

Hi @lfgcampos! Thanks for pointing this issue out and putting your effort to resolve it.
I have few remarks regarding this issue that I would like fixed before merging this PR:

1. There's no issue linked for this PR. Please create one and link it in this PR if such issue does not exist yet. This is our main way of documenting and tracking the changes
2. There seems to be few other cases that potentially could be included in this PR. Please include them or at least address them
3. No tests for either Gradle 9 or other Gradle versions

[lfgcampos]

Hi @lfgcampos! Thanks for pointing this issue out and putting your effort to resolve it. I have few remarks regarding this issue that I would like fixed before merging this PR:

1. There's no issue linked for this PR. Please create one and link it in this PR if such issue does not exist yet. This is our main way of documenting and tracking the changes
2. There seems to be few other cases that potentially could be included in this PR. Please include them or at least address them
3. No tests for either Gradle 9 or other Gradle versions

hi @ewaostrowska, thanks for the comments and review!

1. done, issue created and linked
2. I've covered another 5 ones that I figured would benefit from. There might be more but I can't possibly define a default sensible value without changing behavious
3. Added something, hope it is enough!

Also updated the description with a lot more info 🤞