Fix #3 and #4: populate array/object count and enforce string length …

[ionux]

…limit

#3 - okj_get_array() and okj_get_object() now return an accurate count field by walking the raw JSON text rather than returning 0U unconditionally. Added three static helpers in ok_json.c:

• okj_skip_string(): advances past a quoted JSON string
• okj_count_array_elements(): counts comma-delimited elements at depth 1, skipping nested arrays/objects and string content
• okj_count_object_members(): counts colons at depth 1 (one per member), skipping nested structures and string content

#4 - The string scan loop in okj_parse_value() now breaks when the running length reaches OKJ_MAX_STRING_LEN and returns OKJ_ERROR_MAX_STR_LEN_EXCEEDED instead of scanning unbounded input.

Also changed okj_parse() to propagate the specific error code from okj_parse_value() rather than always returning OKJ_ERROR_PARSING_FAILED, which lets callers distinguish error causes without digging into internals.

Three new tests added (16 total, all passing):

• test_get_array_count: verifies count == 3 for a three-element array
• test_get_object_count: verifies count == 2 for a two-member nested object
• test_string_too_long: verifies OKJ_ERROR_MAX_STR_LEN_EXCEEDED for a 65-character value string (one over the 64-byte limit)

https://claude.ai/code/session_01TFz4uUuUb77evcWUexuxGv