Add basic test samples for 10 missing content types (fixes #662)

[prudhvirapeti]

Summary

Closes #662

Adds manually created basic test samples for 10 common content types that currently have no coverage in tests_data/basic/.

Files Added

Content Type	File	How it was created
cpp	tests_data/basic/cpp/hello.cpp	Manually written C++ program printing primes
go	tests_data/basic/go/hello.go	Manually written Go program printing primes
java	tests_data/basic/java/Hello.java	Manually written Java class printing primes
kotlin	tests_data/basic/kotlin/hello.kt	Manually written Kotlin program printing primes
shell	tests_data/basic/shell/hello.sh	Manually written bash script printing primes
sql	tests_data/basic/sql/query.sql	Manually written SQL with CREATE TABLE, INSERT, and SELECT
xml	tests_data/basic/xml/books.xml	Manually written well-formed XML document
rst	tests_data/basic/rst/document.rst	Manually written reStructuredText with common formatting features
jsonl	tests_data/basic/jsonl/data.jsonl	Manually written JSON Lines file with structured records
scss	tests_data/basic/scss/styles.scss	Manually written SCSS using variables, mixins, and nesting

All samples are clear-cut, easy-to-recognize examples as recommended in the issue — not corner cases.

🤖 Generated with Claude Code

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