Add LCDShiftView library for shift-register based LCD control

[Martin4017]

Introduce LCDShiftView, an enhanced LiquidCrystal-compatible library:

• Custom RS/E/D4–D7 pin mapping via setPins()
• Backlight on/off control via backlight(bool)
• Supports displays > 16×2 and custom characters
• Valid library.properties, version tagged, passes cli lint

See full source: https://github.com/Martin4017/LCDShiftView

[github-actions]

Arduino Lint has suggestions for possible improvements to https://github.com/Martin4017/LCDShiftView:

Linting library in LCDShiftView
WARNING: library.properties url field value * does not have a valid URL format.                                
         See: https://arduino.github.io/arduino-cli/latest/library-specification/#libraryproperties-file-format
         (Rule LP041)                                                                                          
WARNING: Unable to load the library.properties url field: Head "*": unsupported protocol scheme ""             
         See: https://arduino.github.io/arduino-cli/latest/library-specification/#libraryproperties-file-format
         (Rule LP042)                                                                                          

Linter results for project: 0 ERRORS, 2 WARNINGS

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Linting sketch in LCDShiftView/examples/Autoscroll

Linter results for project: no errors or warnings

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Linting sketch in LCDShiftView/examples/Blink

Linter results for project: no errors or warnings

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Linting sketch in LCDShiftView/examples/Cursor

Linter results for project: no errors or warnings

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Linting sketch in LCDShiftView/examples/CustomCharacter

Linter results for project: no errors or warnings

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Linting sketch in LCDShiftView/examples/Display

Linter results for project: no errors or warnings

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Linting sketch in LCDShiftView/examples/HelloWorld

Linter results for project: no errors or warnings

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Linting sketch in LCDShiftView/examples/Scroll

Linter results for project: no errors or warnings

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Linting sketch in LCDShiftView/examples/SerialDisplay

Linter results for project: no errors or warnings

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Linting sketch in LCDShiftView/examples/TextDirection

Linter results for project: no errors or warnings

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Linting sketch in LCDShiftView/examples/setCursor

Linter results for project: no errors or warnings

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Linter results for projects: 0 ERRORS, 2 WARNINGS

[github-actions]

Your submission has now been accepted! Thanks for your contribution to the Arduino Library Manager index.

The library(s) will be available for installation via Library Manager within a day's time.

You can check the logs from the Library Manager indexer for your library(s) here:
http://downloads.arduino.cc/libraries/logs/github.com/Martin4017/LCDShiftView/