feat(tool): Add csaf, openvex and cycloneDx json schemas

Author: JigyasuRajput

cve_bin_tool/schemas/README.txt

@@ -1,3 +1,21 @@
+CVE Binary Tool Local Schema Files
+==================================
+
+This directory contains local schema files for various formats supported by CVE Binary Tool.
+These schemas enable offline validation and faster processing by avoiding network downloads.
+
+Schema Files:
+- bom-1.4.schema.json: CycloneDX BOM format schema
+- csaf_json_schema.json: CSAF VEX format schema  
+- openvex_json_schema.json: OpenVEX format schema
+- cyclonedx_gen.xsd: CycloneDX XML schema (generated)
+- Various other XSD files for XML validation
+
+To update schemas, download the latest versions from official sources:
+- CycloneDX: https://raw.githubusercontent.com/CycloneDX/specification/master/schema/
+- CSAF: https://raw.githubusercontent.com/oasis-tcs/csaf/master/csaf_2.0/json_schema/
+- OpenVEX: https://raw.githubusercontent.com/openvex/spec/main/.schemas/
+
 The cyclconedx_gen.xsd is an amalgamation of cyclonedx.xsd and cyclonedx_spdx.xsd. References
 to spdx namespace in the cyclonedx.xsd is changed to bom.