initial custom coding guidelines

[sajilal711]

Description

What does this PR change/fix and why?

If there is a corresponding JIRA ticket, please ensure it is in the title of the PR.

Test Procedure

How to test this PR (if applicable)

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Other (doesn't fit into the above categories - e.g. documentation updates)

Requires Bitbake Recipe changes?

• The base Bitbake recipe (meta-rdk-ext/recipes-containers/dobby/dobby.bb) must be modified to support the changes in this PR (beyond updating SRC_REV)

[Copilot]

Pull request overview

Introduces initial GitHub Copilot custom coding/review guidelines for the Dobby repository, focusing on logging, plugin lifecycle discipline, onboarding/CI alignment, and spec/schema synchronization.

Changes:

• Added a general instruction set for C/C++/CMake/Shell changes under .github/instructions/.
• Added repository-level Copilot instructions pointing contributors to the custom instruction set and providing a standard “Refer:” link format for review comments.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
.github/instructions/General.instructions.md	Adds the main coding guideline document (logging, lifecycle, onboarding, spec/schema sync) scoped via applyTo.
.github/copilot-instructions.md	Adds top-level Copilot instructions pointing to the custom instruction files and a review-linking convention.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated no new comments.

Comments suppressed due to low confidence (8)

.github/instructions/General.instructions.md:36

• This repeated ### Requirement heading creates another duplicate "Requirement" anchor. Use a subheading level (e.g., #### Requirement) consistently under each rule section.

### Recoverable Error Reporting

### Requirement

.github/instructions/General.instructions.md:51

• This repeated ### Requirement heading creates another duplicate "Requirement" anchor. Use a subheading level (e.g., #### Requirement) consistently under each rule section.

### Null Safety and Pointer Style

### Requirement

.github/instructions/General.instructions.md:59

• This repeated ### Requirement heading creates another duplicate "Requirement" anchor. Use a subheading level (e.g., #### Requirement) consistently under each rule section.

### Plugin Lifecycle Discipline

### Requirement

.github/instructions/General.instructions.md:72

• This repeated ### Requirement heading creates another duplicate "Requirement" anchor. Use a subheading level (e.g., #### Requirement) consistently under each rule section.

### RDK Plugin Hook Contract

### Requirement

.github/instructions/General.instructions.md:82

• This repeated ### Requirement heading creates another duplicate "Requirement" anchor. Use a subheading level (e.g., #### Requirement) consistently under each rule section.

### CMake and Plugin Onboarding Compliance

### Requirement

.github/instructions/General.instructions.md:95

• This repeated ### Requirement heading creates another duplicate "Requirement" anchor. Use a subheading level (e.g., #### Requirement) consistently under each rule section.

### Spec and Schema Synchronization

### Requirement

.github/instructions/General.instructions.md:3

• The applyTo front matter is currently a single comma-separated string, which will be treated as one glob pattern (including commas) rather than multiple patterns. Use a YAML list so each glob is applied independently.

---
applyTo: "**/*.{cpp,h,cc,cxx,hpp},**/CMakeLists.txt,**/*.cmake,**/*.sh"
---

.github/instructions/General.instructions.md:17

• This ### Requirement heading is at the same level as the section heading above it, so it doesn't nest and will also create multiple duplicate "Requirement" anchors throughout the doc. Consider making it a subheading (e.g., #### Requirement) for clearer structure and stable anchors.

This issue also appears in the following locations of the same file:

• line 33
• line 48
• line 56
• line 69
• line 79
• ...and 1 more

### Critical Logging

### Requirement