fix: correct baseUrl interpolation and spurious body null checks

[halotukozak]

Summary

• baseUrl not interpolated: Generated URLs contained ${'$'}{baseUrl} (literal text) instead of ${baseUrl} (interpolation). Every HTTP request was sent to a URL starting with the literal string ${baseUrl} instead of the actual base URL value.
• Spurious if (body != null) on bodyless endpoints: Endpoints without a request body (GETs, DELETEs, etc.) emitted if (body != null) { contentType(Json); setBody(body) }. Since there was no body function parameter, body resolved to HttpRequestBuilder.body (Ktor internals, always non-null), adding a Content-Type: application/json header to every bodyless request.
• Bumps snapshot version to 0.0.3-SNAPSHOT.

Test plan

• New test: endpoint without requestBody does not generate body null check
• New test: generated URL interpolates baseUrl property
• All existing tests pass
• ktlint clean

🤖 Generated with Claude Code

[github-actions]

Coverage Report

Overall Project	96.54%	🍏
Files changed	100%	🍏

File	Coverage
BodyGenerator.kt	95.78%	🍏

[Copilot]

Pull request overview

Fixes two codegen issues in the Ktor client generator: (1) baseUrl was being emitted as a literal string template (\${'$'}{baseUrl}) instead of a real interpolation, and (2) bodyless endpoints were incorrectly emitting if (body != null) { ... setBody(body) ... } due to resolving body to HttpRequestBuilder.body.

Changes:

• Guard JSON body emission so contentType(Json)/setBody(body) is generated only when endpoint.requestBody != null.
• Rework URL template construction so generated request URLs correctly interpolate baseUrl (and path params).
• Add targeted generator tests for both regressions and bump snapshot version to 0.0.3-SNAPSHOT.

Reviewed changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated no comments.

File	Description
core/src/main/kotlin/com/avsystem/justworks/core/gen/client/BodyGenerator.kt	Fixes body emission for bodyless endpoints and corrects baseUrl interpolation in generated URL string templates.
core/src/test/kotlin/com/avsystem/justworks/core/gen/ClientGeneratorTest.kt	Adds regression tests ensuring no body null-check is emitted without a request body and that URLs interpolate baseUrl.
build.gradle.kts	Bumps default snapshot version to 0.0.3-SNAPSHOT.

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