Replace look with lookText' in controller modules

[Purplegaze]

Proposed Changes

Replaces look with lookText in Controllers/Graph and Controllers/Timetable.

BC.pack is replaced with TE.encodeUtf8 in a related function; this is backwards compatible since BC.pack works on ASCII and all ASCII is valid UTF8.

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  • I think this can be considered part of the "Refactored various backend functions to use Text instead of String" line that's already in the changelog for this update

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[coveralls]

Pull Request Test Coverage Report for Build f62b14df-2719-4a15-a9db-973c1de81d2c

Details

• 0 of 2 (0.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 56.524%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
app/Controllers/Graph.hs	0	1	0.0%
app/Export/GetImages.hs	0	1	0.0%

Totals
Change from base Build ac1c0723-45d7-45be-8bea-efc2c6525e84:	0.0%
Covered Lines:	2280
Relevant Lines:	3956

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💛 - Coveralls

[david-yz-liu]

Good work, I just left one inline comment. Please also be sure to update the changelog with a new entry for this refactoring.

[david-yz-liu]

Right now we're using the Aeson decode function, but you should be able to instead use decodeStrictText to simplify the conversions here.

I don't think the encodeUtf8 call is necessary, as the Happstack docs say that the lookText function assumed the data is UTF-8 encoded already.