refactor(skills): remove unused skill_path references from workflows (#19)

skill_path pointed to {project-root}/_bmad/cis/workflows/ which will no
longer exist after the BMAD installer change to stop installing prompts
under _bmad. The variable was defined but never referenced elsewhere in
any workflow.

Author: alexeyv

src/skills/bmad-cis-design-thinking/workflow.md

@@ -25,7 +25,6 @@ Load config from `{main_config}` and resolve:
 
 ### Paths
 
-- `skill_path` = `{project-root}/_bmad/cis/workflows/bmad-cis-design-thinking`
 - `template_file` = `./template.md`
 - `design_methods_file` = `./design-methods.csv`
 - `default_output_file` = `{output_folder}/design-thinking-{date}.md`

src/skills/bmad-cis-innovation-strategy/workflow.md

@@ -25,7 +25,6 @@ Load config from `{main_config}` and resolve:
 
 ### Paths
 
-- `skill_path` = `{project-root}/_bmad/cis/workflows/bmad-cis-innovation-strategy`
 - `template_file` = `./template.md`
 - `innovation_frameworks_file` = `./innovation-frameworks.csv`
 - `default_output_file` = `{output_folder}/innovation-strategy-{date}.md`

src/skills/bmad-cis-problem-solving/workflow.md

@@ -25,7 +25,6 @@ Load config from `{main_config}` and resolve:
 
 ### Paths
 
-- `skill_path` = `{project-root}/_bmad/cis/workflows/bmad-cis-problem-solving`
 - `template_file` = `./template.md`
 - `solving_methods_file` = `./solving-methods.csv`
 - `default_output_file` = `{output_folder}/problem-solution-{date}.md`

src/skills/bmad-cis-storytelling/workflow.md

@@ -25,7 +25,6 @@ Load config from `{main_config}` and resolve:
 
 ### Paths
 
-- `skill_path` = `{project-root}/_bmad/cis/workflows/bmad-cis-storytelling`
 - `template_file` = `./template.md`
 - `story_frameworks_file` = `./story-types.csv`
 - `default_output_file` = `{output_folder}/story-{date}.md`