Draft: Auto collapse single task workflows

[AaronDCole]

These changes partially address #865

Requirements check-list

• I have read CONTRIBUTING.md and added my name as a Code Contributor.
• Contains logically grouped changes (else tidy your branch by rebase).
• Does not contain off-topic changes (use other PRs for other changes).

• Appropriate tests are included (unit and/or functional).
• Already covered by existing tests.
• Does not need tests (UI change).

• Appropriate change log entry included.
• No change log entry required (why? e.g. invisible to users).

• I have opened a documentation PR at cylc/cylc-doc/pull/XXXX.
• No documentation update required.

[codecov-commenter]

Codecov Report

Merging #889 (4827cb1) into master (1dd6dd1) will decrease coverage by 14.95%.
The diff coverage is 14.49%.

@@             Coverage Diff             @@
##           master     #889       +/-   ##
===========================================
- Coverage   91.24%   76.29%   -14.96%     
===========================================
  Files          92       92               
  Lines        1930     1995       +65     
  Branches      114      147       +33     
===========================================
- Hits         1761     1522      -239     
- Misses        143      453      +310     
+ Partials       26       20        -6     

Flag	Coverage Δ
e2e	76.29% <14.49%> (-2.26%)	⬇️
unittests	?

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
src/components/cylc/Drawer.vue	75.00% <ø> (ø)
src/components/cylc/gscan/GScan.vue	72.72% <0.00%> (-21.03%)	⬇️
src/components/cylc/tree/Tree.vue	52.94% <0.00%> (-31.91%)	⬇️
src/views/Table.vue	100.00% <ø> (ø)
src/views/Tree.vue	100.00% <ø> (ø)
src/views/Workflow.vue	92.85% <ø> (ø)
src/components/cylc/table/Table.vue	30.30% <6.66%> (-69.70%)	⬇️
src/components/cylc/table/deltas.js	45.33% <16.66%> (-37.75%)	⬇️
src/components/cylc/gscan/filters.js	78.94% <55.55%> (-21.06%)	⬇️
src/components/cylc/gscan/sort.js	11.11% <0.00%> (-88.89%)	⬇️
... and 30 more

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[oliver-sanders]

Installing and cleaning three runs to see the auto collapse at work:

Nice! I think users will really appreciate this.

Only suggestion is that it might be clearer to keep the tree expand button for collapsed workflows to make it clearer that they have been collapsed? But the slash in the workflow name does cover that nicely.

Something odd is going on with the status boxes:

Otherwise great!

[hjoliver]

Nice 👍

[hjoliver]

Superseded by #938