[java-spring;kotlin-spring] fix values escaping

[Picazsoo]

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---

Summary by cubic

Fixes double-escaping of OpenAPI values in the Spring and Kotlin Spring generators. Values were previously escaped during model construction and again in templates, producing artifacts like <= and \"; they are now preserved raw and escaped once for their output context.

Bug Fixes

• Adds Java and Kotlin string-literal and documentation helpers for annotations, Javadocs, defaults, examples, paths, and enum wire values.
• Preserves UUID parameter serialization and updates generated Spring samples with corrected documentation and full ISO date-time defaults.
• Marks schema defaults that Spring form bindings cannot enforce as "OpenAPI schema default" in generated Javadocs.
• Adds regression coverage; descriptions ending in whitespace may now produce an extra * line in generated Javadocs.

^{Written for commit 312a219. Summary will update on new commits.}

[cubic-dev-ai]

All reported issues were addressed across 341 files

<sub>Note: This PR contains a large number of files. cubic selects up to 200 of the highest-priority eligible files for this review, so some files may not have been reviewed.

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[cubic-dev-ai]

All reported issues were addressed across 339 files

<sub>Note: This PR contains a large number of files. cubic selects up to 200 of the highest-priority eligible files for this review, so some files may not have been reviewed.

Re-trigger cubic</sub>

[cubic-dev-ai]

All reported issues were addressed across 364 files

<sub>Note: This PR contains a large number of files. cubic selects up to 200 of the highest-priority eligible files for this review, so some files may not have been reviewed.
Requires human review: Auto-approval blocked because this review re-detected 1 unresolved issue already reported by Cubic.

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[cubic-dev-ai]

All reported issues were addressed across 379 files

<sub>Note: This PR contains a large number of files. cubic selects up to 200 of the highest-priority eligible files for this review, so some files may not have been reviewed.

Re-trigger cubic</sub>

[cubic-dev-ai]

All reported issues were addressed across 379 files

<sub>Note: This PR contains a large number of files. cubic selects up to 200 of the highest-priority eligible files for this review, so some files may not have been reviewed.
Requires human review: Auto-approval blocked because this review re-detected 1 unresolved issue already reported by Cubic.

Re-trigger cubic</sub>