FBT: Optimize icons blob -4KB DFU, scrub unused icons (#291)

* Unused icons to check later

* Exclude disabled icons from firmware

* Format

* Also report free flash in gh comment

* Fix free flash calc

* Fix?

* Fix??

* Split to next line

* Remove dead icons

* Some spring cleaning of icons cooker

* Improve unused icons script

* Disable icons that cant be used in asset packs

* These will need a workaround for external

* Revert "These will need a workaround for external"

This reverts commit fb23d97952.

* Here's the workaround: split assets lib

now there is "assets" and "fwassets"

firmware links with fwassets and includes all icons
however not all of them are exposed to api

if an app needs a firmware icon not in api, it can use fap_libs=["assets"]
this will link against this dummy assets lib
it only contains the icons that arent exposed to api

this way, an app using assets lib will still benefit from asset packs
but at same time, we can remove pointless icons from dfu blob

* Update changelog

.github/workflows/build.yml

@@ -128,11 +128,22 @@ jobs:
           dfu_size_new=$(du --apparent-size -B 1 artifacts/flipper-z-${TARGET}-full-*.dfu | cut -f1)
           dfu_size_dev=$(du --apparent-size -B 1 dev.dfu | cut -f1)
           dfu_size_diff=$((dfu_size_new - dfu_size_dev))
-          DFU_SIZE=$(echo ${dfu_size_new}B | sed -r 's/^([0-9]+)([0-9]{2})([0-9])B/\1.\2K/')
-          DFU_DIFF=$(echo ${dfu_size_diff}B | sed -r 's/^(-?[0-9]+)([0-9]{2})([0-9])B/\1.\2K/' | sed -r 's/^([^-])/+\1/')
+          DFU_SIZE=$(echo $dfu_size_new | numfmt --to=iec --format=%.2f)
+          DFU_DIFF=$(echo $dfu_size_diff | numfmt --to=iec --format=%.2f | sed -r 's/^([^-])/+\1/')
           echo "DFU_SIZE=$DFU_SIZE" >> $GITHUB_ENV
           echo "DFU_DIFF=$DFU_DIFF" >> $GITHUB_ENV
 
+          tar xzf build/core2_firmware.tgz
+          radio_addr=$(jq -r '.copro.radio.files[0].address' core2_firmware/Manifest.json)
+          flash_base=0x8000000
+          min_gap=$((2 * 4 * 1024))
+          flash_free_total=$((radio_addr - flash_base - dfu_size_new))
+          flash_free_usable=$((flash_free_total - min_gap))
+          FLASH_FREE=$(echo $flash_free_total | numfmt --to=iec --format=%.2f)
+          FLASH_USABLE=$(echo $flash_free_usable | numfmt --to=iec --format=%.2f)
+          echo "FLASH_FREE=$FLASH_FREE" >> $GITHUB_ENV
+          echo "FLASH_USABLE=$FLASH_USABLE" >> $GITHUB_ENV
+
       - name: "Upload artifacts to update server"
         env:
           INDEXER_URL: ${{ secrets.INDEXER_URL }}
@@ -170,6 +181,7 @@ jobs:
             - [☁️ Flipper Lab/App](https://lab.flipper.net/?url=${{secrets.INDEXER_URL}}/builds/firmware/${{steps.names.outputs.branch_name}}/flipper-z-${{steps.names.outputs.default_target}}-update-${{steps.names.outputs.suffix}}.tgz&channel=mntm-${{steps.names.outputs.branch_name}}&version=${{steps.names.outputs.commit_sha}})
             - [📦 qFlipper Package](${{secrets.INDEXER_URL}}/builds/firmware/${{steps.names.outputs.branch_name}}/flipper-z-${{steps.names.outputs.default_target}}-update-${{steps.names.outputs.suffix}}.tgz)
             - DFU Size: `${{ env.DFU_SIZE }}` (`${{ env.DFU_DIFF }}` from dev)
+            - Free Flash: `${{ env.FLASH_FREE }}` (`${{ env.FLASH_USABLE }}` usable)
           edit-mode: replace
 
       - name: Send devbuild webhook