Default wrapped EXPLAIN to hanging indent

[apstndb]

Summary

• enable hanging indent by default for wrapped EXPLAIN and query profile plan rendering
• add CLI_EXPLAIN_HANGING_INDENT as a session-level opt-out for legacy tree-aligned wrapped continuations
• document the new wrapped EXPLAIN behavior and cover both hanging-indent and opt-out rendering paths

Fixes #626

Validation

• go test ./internal/mycli -run 'Test(ProcessPlanNodesUsesHangingIndentForWrappedPlans|newSystemVariablesWithDefaults|SystemVariables_SetGetOperations)'
• mise x -- make check

[github-actions]

Code Metrics Report

📊 View detailed coverage report (available for 7 days)

	main (ddf2ce3)	#635 (ee6fa58)	+/-
Coverage	71.6%	71.6%	+0.0%
Code to Test Ratio	1:1.3	1:1.3	+0.0
Test Execution Time	1m43s	56s	-47s

Details

  |                     | main (ddf2ce3) | #635 (ee6fa58) |  +/-  |
  |---------------------|----------------|----------------|-------|
+ | Coverage            |          71.6% |          71.6% | +0.0% |
  |   Files             |             81 |             81 |     0 |
  |   Lines             |           7338 |           7341 |    +3 |
+ |   Covered           |           5255 |           5259 |    +4 |
+ | Code to Test Ratio  |          1:1.3 |          1:1.3 |  +0.0 |
  |   Code              |          16930 |          16937 |    +7 |
+ |   Test              |          22355 |          22445 |   +90 |
+ | Test Execution Time |          1m43s |            56s |  -47s |

Code coverage of files in pull request scope (70.4% → 70.7%)

Files	Coverage	+/-	Status
internal/mycli/statements_explain_describe.go	61.3%	+0.7%	modified
internal/mycli/statements_query_profile.go	0.0%	0.0%	modified
internal/mycli/system_variables.go	93.9%	0.0%	modified
internal/mycli/var_registry.go	86.9%	+0.0%	modified

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Reported by octocov

[gemini-code-assist]

Code Review

This pull request introduces a new system variable, CLI_EXPLAIN_HANGING_INDENT, which enables hanging indents for wrapped lines in query plans. The changes include updating the documentation, registering the variable with a default value of true, and propagating the setting through the plan processing logic. New tests were added to verify the hanging indent behavior. I have no feedback to provide.

[Copilot]

Pull request overview

This PR updates query plan rendering so wrapped EXPLAIN (and query profile plan output) uses hanging-indent formatting by default, while adding a new session-level system variable to opt out and restore the legacy tree-aligned wrapped continuation lines.

Changes:

• Add CLI_EXPLAIN_HANGING_INDENT (default TRUE) to control hanging-indent behavior for wrapped plan lines.
• Thread the new option through EXPLAIN/EXPLAIN ANALYZE and query-profile plan rendering (processPlanNodes now conditionally applies plantree.WithHangingIndent() when wrapping is enabled).
• Update documentation and add targeted tests to cover both hanging-indent and opt-out rendering paths.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
README.md	Documents the default hanging-indent behavior and adds the new system variable to the README table.
internal/mycli/var_registry.go	Registers CLI_EXPLAIN_HANGING_INDENT in the variable registry.
internal/mycli/system_variables.go	Adds DisplayVars.ExplainHangingIndent and sets the default to true.
internal/mycli/system_variables_test.go	Extends boolean variable set/get coverage to include the new variable.
internal/mycli/statements_query_profile.go	Threads the new option into query profile plan rendering.
internal/mycli/statements_explain_describe.go	Threads the new option into EXPLAIN/EXPLAIN ANALYZE processing and applies plantree.WithHangingIndent() for wrapped output.
internal/mycli/statements_explain_describe_test.go	Adds tests validating hanging-indent vs legacy wrapped continuation formatting.
internal/mycli/main_test.go	Updates default expectations/ignores to account for the new display variable.
docs/query_plan.md	Documents CLI_EXPLAIN_HANGING_INDENT and its default/opt-out behavior.

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[Copilot]

Pull request overview

Copilot reviewed 9 out of 9 changed files in this pull request and generated 2 comments.

[Copilot]

Pull request overview

Copilot reviewed 9 out of 9 changed files in this pull request and generated 1 comment.

[Copilot]

Pull request overview

Copilot reviewed 9 out of 9 changed files in this pull request and generated no new comments.

[apstndb]

/gemini review

[apstndb]

/gemini review

[gemini-code-assist]

Code Review

This pull request introduces a new system variable, CLI_EXPLAIN_HANGING_INDENT, which enables hanging indents for wrapped query plan lines in EXPLAIN, EXPLAIN ANALYZE, and query profile outputs. The changes include updating the system variable registry, modifying the query plan processing logic to support this new display option, and adding comprehensive tests to verify the behavior. Documentation in the README and query plan guide has also been updated to reflect this new configuration option. I have no feedback to provide as there were no review comments to evaluate.

[gemini-code-assist]

Code Review

This pull request introduces a new system variable, CLI_EXPLAIN_HANGING_INDENT, which enables hanging indents for wrapped query plan lines in EXPLAIN, EXPLAIN ANALYZE, and query profile outputs. The changes include updating the system variable registry, modifying the plan processing logic to support this formatting option, and adding comprehensive tests to verify the new behavior. Documentation in the README and query plan guide has also been updated to reflect this new feature. I have no feedback to provide.