Ensure predictable Ballerina dependency resolution in workflows

[nipunayf]

Purpose

Currently, the only way to lock transitive dependency versions is by specifying the required version in Ballerina.toml and building with the --sticky flag. This PR updates the existing usage of bal pull to follow this approach.

Fixes wso2/product-ballerina-integrator#1245

[Copilot]

Pull Request Overview

This PR ensures predictable Ballerina dependency resolution by replacing the use of bal pull with a Ballerina.toml file specifying dependency versions with the --sticky flag for builds.

• Removes version definitions from gradle.properties and individual module bal pull commands
• Creates a centralized dependency management approach using Ballerina.toml with sticky builds
• Temporarily disables Mistral AI provider tests due to dependency resolution issues

Reviewed Changes

Copilot reviewed 7 out of 8 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
gradle.properties	Removes version variables for Ballerinax modules and fixes naming inconsistencies
build-config/ballerina_dependencies/Ballerina.toml	Adds centralized dependency configuration with sticky build option
build-config/ballerina_dependencies/main.bal	Creates placeholder file with imports for all required dependencies
flow-model-generator/modules/flow-model-generator-ls-extension/build.gradle	Removes individual bal pull commands for modules
GetNodeTemplateTest.java	Comments out Mistral test case with tracking reference
CodeGenerationTest.java	Comments out Mistral test case with tracking reference
architecture-model-generator/modules/architecture-model-generator-ls-extension/build.gradle	Adds --sticky flag to tool pull commands

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