Feature/configuration

[AdamWagner]

This is a big one!
Much-improved configurability is the primary new feature. There are 3 configuration themes:

Appearance
Customize indicator sizing, coloring, positioning, roundness, animation durations, form factor, etc

Features
Enable/disable fuzzy frame detection, click-to-focus, the hacky workaround for Hammerspoon/hammerspoon#2400, or – coming soon – window titles.
You'll no longer have to put up with bugs in a feature that you don't even use ;-)

Paths
An easier way to specify paths to binaries & scripts without mucking around in the stackline source.

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Config validation & live-tweaking

All config values can be edited while stackline is running (this should seem familiar from yabai).

Values can be set using the hs cli tool:

hs -c "stackline.config:set('appearance.radius', 3)"

… or the ipc port:

echo ":appearance.radius:3` | hs -m stackline-config

All config fields support get(key), set(key, val), and getOrSet(key, [val]).
In addition, boolean fields support toggle()

You can get and set nested config fields via a dot-separated path, like this: features.fzyFrameDetection.enabled

Config fields are typed and validated on initialization and when live-set.
stackline will notify you If you can't remember the exact path to a config variable:

---

The default config

c = {}
c.paths = {}
c.appearance = {}
c.features = {}

-- Paths
c.paths.getStackIdxs                  = hs.configdir .. '/stackline/bin/yabai-get-stack-idx'
c.paths.jq                            = '/usr/local/bin/jq'
c.paths.yabai                         = '/usr/local/bin/yabai'

-- Appearance
c.appearance.color                    = { white = 0.90 }
c.appearance.alpha                    = 1
c.appearance.dimmer                   = 2.5                 -- larger numbers increase contrast b/n focused & unfocused state
c.appearance.iconDimmer               = 1.1                 -- custom dimmer for icon
c.appearance.showIcons                = true
c.appearance.size                     = 32
c.appearance.radius                   = 3
c.appearance.padding                  = 4
c.appearance.iconPadding              = 4
c.appearance.pillThinness             = 6

c.appearance.vertSpacing              = 1.2

c.appearance.offset                   = {}
c.appearance.offset.y                 = 2
c.appearance.offset.x                 = 4

c.appearance.shouldFade               = true
c.appearance.fadeDuration             = 0.2

-- Features
c.features.clickToFocus               = true
c.features.hsBugWorkaround            = true

c.features.fzyFrameDetect             = {}
c.features.fzyFrameDetect.enabled     = true
c.features.fzyFrameDetect.fuzzFactor  = 15                  -- window frame dimensions will be rounded to nearest fuzzFactor

c.features.winTitles                  = 'not_implemented'    -- false, true, 'when_switching', 'not_implemented'
c.features.dynamicLuminosity          = 'not_implemented'    -- false, true, 'not_implemented'