feat: add args for custom volume mount paths

[rswanson]

1. Added three optional fields to SignetNodeComponentArgs in types.go:
   - SignetNodeDataMountPath (defaults to /root/.local/share/reth)
   - RollupDataMountPath (defaults to /root/.local/share/exex)
   - ExecutionJwtMountPath (defaults to /etc/reth/execution-jwt)
2. Created default constants in constants.go for the default mount paths
3. Added ApplyDefaults() method in validation.go that sets default values if not provided
4. Updated internal types to include the new mount path fields
5. Modified the conversion function toInternal() to include the new fields
6. Updated NewSignetNode() in signet_node.go to:
   - Call ApplyDefaults() before validation
   - Use the configurable mount paths instead of hardcoded values
7. Added comprehensive tests for the new functionality

[Copilot]

Pull Request Overview

This PR adds configurable mount paths for SignetNode components, allowing users to customize where volumes are mounted instead of using hardcoded paths. The changes enable better flexibility for deployment scenarios where standard paths may not be suitable.

• Added three optional fields for custom volume mount paths with sensible defaults
• Implemented default value application through an ApplyDefaults() method
• Updated the SignetNode component to use configurable paths instead of hardcoded values

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
pkg/signet_node/types.go	Added mount path fields to component args and internal types
pkg/signet_node/constants.go	Defined default mount path constants
pkg/signet_node/validation.go	Implemented ApplyDefaults() method to set default values
pkg/signet_node/signet_node.go	Updated component creation to use configurable mount paths
pkg/signet_node/validation_test.go	Added comprehensive tests for the new ApplyDefaults functionality

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[rswanson]

• feat: add args for custom volume mount paths #44 👈 (View in Graphite)
• main

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